In 1903, Josiah White III bought a parcel of land near Ohio Avenue and the boardwalk and built the Queen Anne style Marlborough House. The hotel was a hit and, in 1905–06, he chose to expand the hotel and bought another parcel of land next door to his Marlborough House. In an effort to make his new hotel a source of conversation, White hired the architectural firm of Price and McLanahan. The firm made use of reinforced concrete, a new building material invented by Jean-Louis Lambot in 1848 (Joseph Monier received the patent in 1867). The hotel's Spanish and Moorish themes, capped off with its signature dome and chimneys, represented a step forward from other hotels that had a classically designed influence. White named the new hotel the Blenheim and merged the two hotels into the Marlborough-Blenheim. Bally's Atlantic City was later constructed at this location.

In what year did Josiah White III by land to build a hotel?

What was the name of the hotel built by Josiah White III?

Marlborough House

In what style was the Malborough House buit?

Queen Anne

In what year was reinforced concrete invented?

What was the name of the second hotel built by Josiah White III?

Blenheim


The Traymore Hotel was located at the corner of Illinois Avenue and the boardwalk. Begun in 1879 as a small boarding house, the hotel grew through a series of uncoordinated expansions. By 1914, the hotel's owner, Daniel White, taking a hint from the Marlborough-Blenheim, commissioned the firm of Price and McLanahan to build an even bigger hotel. Rising 16 stories, the tan brick and gold-capped hotel would become one of the city's best-known landmarks. The hotel made use of ocean-facing hotel rooms by jutting its wings farther from the main portion of the hotel along Pacific Avenue.

What was the name of the hotel located at the corner of Illinois Avenue and the boardwalk?

The Traymore Hotel

What year was The Traymore Hotel begun?

Who was the owner of The Traymore Hotel?

Daniel White

How many stories was The Traymore Hotel after its renovation?

What was the name of the firm commissioned to build The Traymore Hotel?

Price and McLanahan


One by one, additional large hotels were constructed along the boardwalk, including the Brighton, Chelsea, Shelburne, Ambassador, Ritz Carlton, Mayflower, Madison House, and the Breakers. The Quaker-owned Chalfonte House, opened in 1868, and Haddon House, opened in 1869, flanked North Carolina Avenue at the beach end. Their original wood-frame structures would be enlarged, and even moved closer to the beach, over the years. The modern Chalfonte Hotel, eight stories tall, opened in 1904. The modern Haddon Hall was built in stages and was completed in 1929, at eleven stories. By this time, they were under the same ownership and merged into the Chalfonte-Haddon Hall Hotel, becoming the city's largest hotel with nearly 1,000 rooms. By 1930, the Claridge, the city's last large hotel before the casinos, opened its doors. The 400-room Claridge was built by a partnership that included renowned Philadelphia contractor John McShain. At 24 stories, it would become known as the "Skyscraper By The Sea." The city became known as the "The World's Playground.

What year did the Quaker-owned Chalfonte House open?

What year did the Haddon House open?

How many stories was the modern Chalfonte Hotel when it opened in 1904?

eight

How many rooms were in the merged Chalfonte-Haddon Hall Hotel?

nearly 1,000

What was the name given to the 24 story tall, 400-room Claridge?

Skyscraper By The Sea


In 1883, salt water taffy was conceived in Atlantic City by David Bradley. The traditional story is that Bradley's shop was flooded after a major storm, soaking his taffy with salty Atlantic Ocean water. He sold some "salt water taffy" to a girl, who proudly walked down to the beach to show her friends. Bradley's mother was in the back of the store when the sale was made, and loved the name, and so salt water taffy was born.

In what year was salt water taffy conceived?

Who was the creator of salt water taffy?

David Bradley

What happened to David Bradley's shop that led to the creation of salt water taffy?

Bradley's shop was flooded after a major storm

Who did Bradley sell salt water taffy to for the first time?

a girl

Where did the water come from for the creation of the first salt water taffy?

Atlantic Ocean


The 1920s, with tourism at its peak, are considered by many historians as Atlantic City's golden age. During Prohibition, which was enacted nationally in 1919 and lasted until 1933, much liquor was consumed and gambling regularly took place in the back rooms of nightclubs and restaurants. It was during Prohibition that racketeer and political boss Enoch L. "Nucky" Johnson rose to power. Prohibition was largely unenforced in Atlantic City, and, because alcohol that had been smuggled into the city with the acquiescence of local officials could be readily obtained at restaurants and other establishments, the resort's popularity grew further. The city then dubbed itself as "The World's Playground". Nucky Johnson's income, which reached as much as $500,000 annually, came from the kickbacks he took on illegal liquor, gambling and prostitution operating in the city, as well as from kickbacks on construction projects.

What years do many historians consider Atlantic City's golden age?

What year was Prohibition enacted nationally?

During Prohibition what name was given to Atlantic City?

The World's Playground

During Prohibition how high was Nucky Johnson's income?

as much as $500,000 annually

How long did Prohibition last?

until 1933


During this time, Atlantic City was under the mayoral reign of Edward L. Bader, known for his contributions to the construction, athletics and aviation of Atlantic City. Despite the opposition of many others, he purchased land that became the city's municipal airport and high school football stadium, both of which were later named Bader Field in his honor. He led the initiative, in 1923, to construct the Atlantic City High School at Albany and Atlantic Avenues. Bader, in November 1923, initiated a public referendum, during the general election, at which time residents approved the construction of a Convention Center. The city passed an ordinance approving a bond issue for $1.5 million to be used for the purchase of land for Convention Hall, now known as the Boardwalk Hall, finalized September 30, 1924. Bader was also a driving force behind the creation of the Miss America competition.

During the 1920s, who was the mayor of Atlantic City?

Edward L. Bader

What three contributions to Atlantic City was Edward L. Bader known for?

construction, athletics and aviation

What year did Edward L. Bader lead the initiative to construct the Atlantic City High School?

How much was the bond for that was to be used to purchase land for a Convention Center?

$1.5 million

What year was Boardwalk Hall finished?


From May 13 to May 16 in 1929, Johnson hosted a conference for organized crime figures from all across America. The men who called this meeting were Masseria family lieutenant Charles "Lucky" Luciano and former Chicago South Side Gang boss Johnny "the Fox" Torrio, with heads of the Bugs and Meyer Mob, Meyer Lansky and Benjamin Siegel, being used as muscle for the meeting.

Who was a meeting organized for in 1929 in Atlantic City?

organized crime figures from all across America

What family was Charles

Charles "Lucky" Luciano and former Chicago South Side Gang boss Johnny "the Fox" Torrio

In what year was there a conference for organized crime figures in Atlantic City?

For which family was Charles "Lucky" Luciano a lieutenant?

Masseria family

What was Johnny Torrio's nickname?

the Fox

What was Charles Luciano's nickname?

Lucky

Who was a former Chicago South Side Gang boss?

Johnny "the Fox" Torrio


Like many older east coast cities after World War II, Atlantic City became plagued with poverty, crime, corruption, and general economic decline in the mid-to-late 20th century. The neighborhood known as the "Inlet" became particularly impoverished. The reasons for the resort's decline were multi-layered. First of all, the automobile became more readily available to many Americans after the war. Atlantic City had initially relied upon visitors coming by train and staying for a couple of weeks. The car allowed them to come and go as they pleased, and many people would spend only a few days, rather than weeks. Also, the advent of suburbia played a huge role. With many families moving to their own private houses, luxuries such as home air conditioning and swimming pools diminished their interest in flocking to the luxury beach resorts during the hot summer. But perhaps the biggest factor in the decline in Atlantic City's popularity came from cheap, fast jet service to other premier resorts, such as Miami Beach and the Bahamas.

Which Atlantic City neighborhood became particularly impoverished in the mid-to-late 20th century?

the "Inlet"

What was the biggest factor in the decline in Atlantic City's popularity?

cheap, fast jet service

What were two other locations people began to fly to instead of going to Atlantic City?

Miami Beach and the Bahamas

After the war, what form of transportation became more readily available to many Americans?

automobile

What two luxuries that people could have at their own homes led to a diminished interest in luxury beach resorts?

home air conditioning and swimming pools


The city hosted the 1964 Democratic National Convention which nominated Lyndon Johnson for President and Hubert Humphrey as Vice President. The convention and the press coverage it generated, however, cast a harsh light on Atlantic City, which by then was in the midst of a long period of economic decline. Many felt that the friendship between Johnson and Governor of New Jersey Richard J. Hughes led Atlantic City to host the Democratic Convention.

What event was hosted by Atlantic City in 1964?

Democratic National Convention

Who was nominated for President during the 1964 Democratic National Convention?

Lyndon Johnson

Who was nominated for Vice President during the 1964 Democratic National Convention?

Hubert Humphrey

Who was the Governor of New Jersey in 1964?

Richard J. Hughes

Despite being in the midst of a long period of economic decline many felt that the Convention was only held in Atlantic city because of a friendship between what two men?

Johnson and Governor of New Jersey Richard J. Hughes


By the late 1960s, many of the resort's once great hotels were suffering from embarrassing vacancy rates. Most of them were either shut down, converted to cheap apartments, or converted to nursing home facilities by the end of the decade. Prior to and during the advent of legalized gaming, many of these hotels were demolished. The Breakers, the Chelsea, the Brighton, the Shelburne, the Mayflower, the Traymore, and the Marlborough-Blenheim were demolished in the 1970s and 1980s. Of the many pre-casino resorts that bordered the boardwalk, only the Claridge, the Dennis, the Ritz-Carlton, and the Haddon Hall survive to this day as parts of Bally's Atlantic City, a condo complex, and Resorts Atlantic City. The old Ambassador Hotel was purchased by Ramada in 1978 and was gutted to become the Tropicana Casino and Resort Atlantic City, only reusing the steelwork of the original building. Smaller hotels off the boardwalk, such as the Madison also survived.

By what years were many of the great hotels suffering from high vacancy rates?

the late 1960s

Prior to and during the advent of legalized gaming, what happened to many of the hotels in Atlantic City?

demolished

When were many of the large hotels demolished?

1970s and 1980s

After the Ambassador Hotel was gutted what did it become?

Tropicana Casino and Resort Atlantic City

Who purchased the old Ambassador Hotel in 1978?

Ramada


In an effort at revitalizing the city, New Jersey voters in 1976 passed a referendum, approving casino gambling for Atlantic City; this came after a 1974 referendum on legalized gambling failed to pass. Immediately after the legislation passed, the owners of the Chalfonte-Haddon Hall Hotel began converting it into the Resorts International. It was the first legal casino in the eastern United States when it opened on May 26, 1978. Other casinos were soon constructed along the Boardwalk and, later, in the marina district for a total of eleven today. The introduction of gambling did not, however, quickly eliminate many of the urban problems that plagued Atlantic City. Many people have suggested that it only served to exacerbate those problems, as attested to by the stark contrast between tourism intensive areas and the adjacent impoverished working-class neighborhoods. In addition, Atlantic City has been less popular than Las Vegas, as a gambling city in the United States. Donald Trump helped bring big name boxing bouts to the city to attract customers to his casinos. The boxer Mike Tyson had most of his fights in Atlantic City in the 1980s, which helped Atlantic City achieve nationwide attention as a gambling resort. Numerous highrise condominiums were built for use as permanent residences or second homes. By end of the decade it was one of the most popular tourist destinations in the United States.

In what year did New Jersey voters pass a referendum approving casino gambling for Atlantic City?

The owners of the Chalfonte-Haddon Hall Hotel converted it into what?

Resorts International

What was the name of the first legal casino in the eastern United States?

Resorts International

What year did Resorts International open?

How many casinos are there in Atlantic City today?

eleven


With the redevelopment of Las Vegas and the opening of two casinos in Connecticut in the early 1990s, along with newly built casinos in the nearby Philadelphia metro area in the 2000s, Atlantic City's tourism began to decline due to its failure to diversify away from gaming. Determined to expand, in 1999 the Atlantic City Redevelopment Authority partnered with Las Vegas casino mogul Steve Wynn to develop a new roadway to a barren section of the city near the Marina. Nicknamed "The Tunnel Project", Steve Wynn planned the proposed 'Mirage Atlantic City' around the idea that he would connect the $330 million tunnel stretching 2.5 miles (4.0 km) from the Atlantic City Expressway to his new resort. The roadway was later officially named the Atlantic City-Brigantine Connector, and funnels incoming traffic off of the expressway into the city's marina district and Brigantine, New Jersey.

Atlantic City's tourism began to decline due to what failure?

to diversify away from gaming

Who did the Atlantic City Redevelopment Authority partner with in 1999?

Steve Wynn

Why did the Atlantic City Redevelopment Authority partner with Steve Wynn?

to develop a new roadway

What was the project involving Steve Wynn nicknamed?

The Tunnel Project

"The Tunnel Project" was later officially named what?

Atlantic City-Brigantine Connector


Although Wynn's plans for development in the city were scrapped in 2002, the tunnel opened in 2001. The new roadway prompted Boyd Gaming in partnership with MGM/Mirage to build Atlantic City's newest casino. The Borgata opened in July 2003, and its success brought an influx of developers to Atlantic City with plans for building grand Las Vegas style mega casinos to revitalize the aging city.

In what year did the tunnel open?

What was the name of Atlantic City's newest casino?

The Borgata

When did The Borgata open?

July 2003

In what year was Wynn's plans for development scrapped?

The new roadway prompted a partnership between which two companies?

Boyd Gaming in partnership with MGM/Mirage


Owing to economic conditions and the late 2000s recession, many of the proposed mega casinos never went further than the initial planning stages. One of these developers was Pinnacle Entertainment, who purchased the Sands Atlantic City, only to close it permanently November 11, 2006. The following year, the resort was demolished in a dramatic, Las Vegas styled implosion, the first of its kind in Atlantic City. While Pinnacle Entertainment intended to replace it with a $1.5–2 billion casino resort, the company canceled its construction plans and plans to sell the land. The biggest disappointment was when MGM Resorts International announced that it would pull out of all development for Atlantic City, effectively ending their plans for the MGM Grand Atlantic City.

When did the Sands Atlantic City close permanently?

November 11, 2006

What happened to the Sands Atlantic City a year after it closed?

demolished in a dramatic, Las Vegas styled implosion

What did Pinnacle Entertainment intend to replace the Sands Atlantic City with?

$1.5–2 billion casino resort

Why did many of the proposed mega casinos never get further than the initial planning stages?

economic conditions and the late 2000s recession

Who purchased the Sands Atlantic City?

Pinnacle Entertainment


In 2006, Morgan Stanley purchased 20 acres (8.1 ha) directly north of the Showboat Atlantic City Hotel and Casino for a new $2 billion plus casino resort. Revel Entertainment Group was named as the project's developer for the Revel Casino. Revel was hindered with many problems, with the biggest setback to the company being in April 2010 when Morgan Stanley, the owner of 90% of Revel Entertainment Group, decided to discontinue funding for continued construction and put its stake in Revel up for sale. Early in 2010 the New Jersey state legislature passed a bill offering tax incentives to attract new investors and complete the job, but a poll by Fairleigh Dickinson University's PublicMind released in March 2010 showed that three of five voters (60%) opposed the legislation, and two of three of those who opposed it "strongly" opposed it. Ultimately, Governor Chris Christie offered Revel $261 million in state tax credits to assist the casino once it opened. As of March 2011[update], Revel had completed all of the exterior work and had continued work on the interior after finally receiving the funding necessary to complete construction. It had a soft opening in April 2012, and was fully open by May 2012. Ten months later, in February 2013, after serious losses and a write-down in the value of the resort from $2.4 billion to $450 million, Revel filed for Chapter 11 bankruptcy. It was restructured but still could not carry on and re-entered bankruptcy on June 19, 2014. It was put up for sale, however as no suitable bids were received the resort closed its doors on September 2, 2014.

In what year did Morgan Stanley purchase land for a new casino resort?

How much land did Morgan Stanley purchase?

20 acres

Who was named as the developer for Morgan Stanley's casino resort?

Revel Entertainment Group

What percentage of ownership did Morgan Stanley hold in Revel Entertainment Group?

Who offered Revel $261 million in state tax credits?

Governor Chris Christie


In the wake of the closures and declining revenue from casinos, Governor Christie said in September 2014 that the state would consider a 2015 referendum to end the 40-year-old monopoly that Atlantic City holds on casino gambling and allowing gambling in other municipalities. With casino revenue declining from $5.2 billion in 2006 to $2.9 billion in 2013, the state saw a drop in money from its 8% tax on those earnings, which is used to fund programs for senior citizens and the disabled.

How long had Atlantic City held a monopoly on casino gambling?

Who said that the state would consider a referendum to end the monopoly that Atlantic City holds on casino gambling?

Governor Christie

When did Governor Christie say that the state would consider a referendum?

September 2014

How much was casino revenue in 2006?

$5.2 billion

How much was casino revenue in 2013?

$2.9 billion


"Superstorm Sandy" struck Atlantic City on October 29, 2012, causing flooding and power-outages but left minimal damage to any of the tourist areas including the Boardwalk and casino resorts, despite widespread belief that the city's boardwalk had been destroyed. The source of the misinformation was a widely circulated photograph of a damaged section of the Boardwalk that was slated for repairs, prior to the storm, and incorrect news reports at the time of the disaster. The storm produced an all-time record low barometric pressure reading of 943 mb (27.85") for not only Atlantic City, but the state of New Jersey.

When did "Superstorm Sandy" strike Atlantic City?

October 29, 2012

"Superstorm Sandy" produced an all-time record low barometric pressure reading of what?

943 mb

Although "Superstorm Sandy" left minimal damage to any of the tourist areas it did cause what two other things to occur?

flooding and power-outages

What was the source of the misinformation concerning damage to the city's boardwalk?

photograph

Why was there a photo of the Boardwalk if it wasn't actually damaged in the storm?

the Boardwalk that was slated for repairs, prior to the storm


According to the United States Census Bureau, the city had a total area of 17.037 square miles (44.125 km2), including 10.747 square miles (27.835 km2) of land and 6.290 square miles (16.290 km2) of water (36.92%).

According to the United States Census Bureau, what is the total area in square miles?

17.037 square miles

What is the area of land?

10.747 square miles

What is the area of water?

6.290 square miles

What percentage of the city is made up of water?

What organization provided data detailing the size of the city?

United States Census Bureau


Unincorporated communities, localities and place names located partially or completely within the city include Chelsea, City Island, Great Island and Venice Park.

Besides Chelsea, City Island, and Great Island, what other community, locality, or place name is included in the city?

Venice Park

Besides Chelsea, City Island, and Venice Park, what other community, locality, or place name is included in the city?

Great Island

Besides Chelsea, Venice Park, and Great Island, what other community, locality, or place name is included in the city?

City Island

Besides Venice Park, City Island, and Great Island, what other community, locality, or place name is included in the city?

Chelsea

Besides localities and place names, what else is located partically or completely within the city?

Unincorporated communities


Summers are typically warm and humid with a July daily average of 75.6 °F (24.2 °C). During this time, the city gets a sea breeze off the ocean that often makes daytime temperatures much cooler than inland areas, making Atlantic City a prime place for beating the summer heat from June through September. Average highs even just a few miles west of Atlantic City exceed 85 °F (29 °C) in July. Near the coast, temperatures reach or exceed 90 °F (32 °C) on an average of only 6.8 days a year, but this reaches 21 days at nearby Atlantic City Int'l.[a] Winters are cool, with January averaging 35.5 °F (2 °C). Spring and autumn are erratic, although they are usually mild with low humidity. The average window for freezing temperatures is November 20 to March 25, allowing a growing season of 239 days. Extreme temperatures range from −9 °F (−23 °C) on February 9, 1934 to 104 °F (40 °C) on August 7, 1918.[b]

What is the daily average temperature in July?

75.6 °F

Atlantic City is a prime place to beat the heat from June through what month?

September

What is the average temperature for January in Atlantic City?

35.5 °F

How many days long is the growing season?

239 days

What is the extreme low temperature of Atlantic City?

−9 °F


Annual precipitation is 40 inches (1,020 mm) which is fairly spread throughout the year. Owing to its proximity to the Atlantic Ocean and its location in South Jersey, Atlantic City receives less snow than a good portion of the rest of New Jersey. Even at the airport, where low temperatures are often much lower than along the coast, snow averages only 16.5 inches (41.9 cm) each winter. It is very common for rain to fall in Atlantic City while the northern and western parts of the state are receiving snow.

How many inches of precipitation does Atlantic City receive annually?

40 inches

What is the average number of inches of snow received at the airport annually?

16.5 inches

Atlantic City's lack of snowfall is due to its location in South Jersey and its proximaty to which body of water?

Atlantic Ocean

Atlantic City's lack of snowfall is due to its proximity to the Atlantic Ocean and its location where?

South Jersey

Atlantic City is different from the northern and western parts of the state in the winter due to its tendency to receive which type of precipitation?

rain


At the 2010 United States Census, there were 39,558 people, 15,504 households, and 8,558 families residing in the city. The population density was 3,680.8 per square mile (1,421.2/km2). There were 20,013 housing units at an average density of 1,862.2 per square mile (719.0/km2). The racial makeup of the city was 26.65% (10,543) White, 38.29% (15,148) Black or African American, 0.61% (242) Native American, 15.55% (6,153) Asian, 0.05% (18) Pacific Islander, 14.03% (5,549) from other races, and 4.82% (1,905) from two or more races. Hispanics or Latinos of any race were 30.45% (12,044) of the population.

How many people were residing in Atlantic City during the 2010 United States Census?

How many housing units were in Atlantic City during the 2010 United States Census?

During the 2010 United States Census what percentage of Atlantic City's population was Hispanic or Latino?

During the 2010 United States Census what percentage of Atlantic City's population was White?

How many families were residing in Atlantic City during the 2010 United States Census?


There were 15,504 households, of which 27.3% had children under the age of 18 living with them, 25.9% were married couples living together, 22.2% had a female householder with no husband present, and 44.8% were non-families. 37.5% of all households were made up of individuals, and 14.3% had someone living alone who was 65 years of age or older. The average household size was 2.50 and the average family size was 3.34.

How many households were there in Atlantic City during the 2010 United States Census?

What percentage of households in Atlantic City had children under the age of 18 living with them?

What percentage of households in Atlantic City were comprised of non-families?

What percentage of households in Atlantic City were made up of individuals?


In the city, 24.6% of the population were under the age of 18, 10.2% from 18 to 24, 26.8% from 25 to 44, 25.8% from 45 to 64, and 12.7% who were 65 years of age or older. The median age was 36.3 years. For every 100 females there were 96.2 males. For every 100 females age 18 and over, there were 94.4 males.

What percentage of the population was under the age of 18?

What percentage of the population was 65 years of age or older?

What was the median age?

36.3 years


The Census Bureau's 2006–2010 American Community Survey showed that (in 2010 inflation-adjusted dollars) median household income was $30,237 (with a margin of error of +/- $2,354) and the median family income was $35,488 (+/- $2,607). Males had a median income of $32,207 (+/- $1,641) versus $29,298 (+/- $1,380) for females. The per capita income for the city was $20,069 (+/- $2,532). About 23.1% of families and 25.3% of the population were below the poverty line, including 36.6% of those under age 18 and 16.8% of those age 65 or over.

How much was the median household income according to the American Community Survey?

How much was the median family income according to the American Community Survey?

How much was the median income for males according to the American Community Survey?

What percentage of the population was below the poverty line?


As of the 2000 United States Census there were 40,517 people, 15,848 households, and 8,700 families residing in the city. The population density was 3,569.8 people per square mile (1,378.3/km2). There were 20,219 housing units at an average density of 1,781.4 per square mile (687.8/km2). The racial makeup of the city was 44.16% black or African American, 26.68% White, 0.48% Native American, 10.40% Asian, 0.06% Pacific Islander, 13.76% other races, and 4.47% from two or more races. 24.95% of the population were Hispanic or Latino of any race. 19.44% of the population was non-Hispanic whites.

According to the 2000 United States Census, how many people were living in Atlantic City?

According to the 2000 United States Census, what was the population density?

3,569.8 people per square mile

According to the 2000 United States Census, how many housing units were there in Atlantic City?

According to the 2000 United States Census, what percentage of the population of Atlantic City were Hispanic or Latino?

According to the 2000 United States Census, what percentage of the population of Atlantic City were white?


There were 15,848 households out of which 27.7% had children under the age of 18 living with them, 24.8% were married couples living together, 23.2% had a female householder with no husband present, and 45.1% were non-families. 37.2% of all households were made up of individuals and 15.4% had someone living alone who was 65 years of age or older. The average household size was 2.46 and the average family size was 3.26.

How many households had children under the age of 18 living with them?

How many households were there in Atlantic City?

How many households were made up of individuals?

What was the average household size in Atlantic City?

What was the average family size in Atlantic City?


In the city the population was spread out with 25.7% under the age of 18, 8.9% from 18 to 24, 31.0% from 25 to 44, 20.2% from 45 to 64, and 14.2% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 96.1 males. For every 100 females age 18 and over, there were 93.2 males.

What was the median age of Atlantic City?

35 years

For every 100 females, how many males were there?

For every 100 females age 18 and over, how many males were there?

What percentage of the population of Atlantic City was under the age of 18?

What percentage of the population of Atlantic City was 65 years of age or older?


The median income for a household in the city was $26,969, and the median income for a family was $31,997. Males had a median income of $25,471 versus $23,863 for females. The per capita income for the city was $15,402. About 19.1% of families and 23.6% of the population were below the poverty line, including 29.1% of those under age 18 and 18.9% of those age 65 or over.

What was the median income for a household in the city?

What was the median income for a family in the city?

What was the per capita income for the city?

What percentage of families in the city were living below the poverty line?

What percentage of the population in the city were living below the poverty line?


As of September 2014, the greater Atlantic City area has one of the highest unemployment rates in the country at 13.8%, out of labor force of around 141,000.

As of September 2014, the greater Atlantic City area had one of the highest rates in the country of what?

unemployment

What was the unemployment rate for the greater Atlantic City area, as of September 2014?

As of September 2014, what was the overall size of the labor force of the greater Atlantic City area?

Out of a labor force of about 141,000 what was the unemployment rate?


In July 2010, Governor Chris Christie announced that a state takeover of the city and local government "was imminent". Comparing regulations in Atlantic City to an "antique car", Atlantic City regulatory reform is a key piece of Gov. Chris Christie's plan, unveiled on July 22, to reinvigorate an industry mired in a four-year slump in revenue and hammered by fresh competition from casinos in the surrounding states of Delaware, Pennsylvania, Connecticut, and more recently, Maryland. In January 2011, Chris Christie announced the Atlantic City Tourism District, a state-run district encompassing the boardwalk casinos, the marina casinos, the Atlantic City Outlets, and Bader Field. Fairleigh Dickinson University's PublicMind poll surveyed New Jersey voters' attitudes on the takeover. The February 16, 2011 survey showed that 43% opposed the measure while 29% favored direct state oversight. Interestingly, the poll also found that even South Jersey voters expressed opposition to the plan; 40% reported they opposed the measure and 37% reported they were in favor of it.

In 2010, who stated that a state takeover of the city and local government of Atlantic City was imminent?

Governor Chris Christie

What item were the regulations in Atlantic City compared to?

antique car

What was the name of the district that would encompass the boardwalk casinos, the marina casinos, the Atlantic City Outlets, and Bader Field?

Atlantic City Tourism District

According to a poll, what percentage of New Jersey voters opposed the takeover of Atlantic City by the state?

According to a poll, what percentage of New Jersey voters favored the takeover of Atlantic City by the state?


On April 29, 2011, the boundaries for the state-run tourism district were set. The district would include heavier police presence, as well as beautification and infrastructure improvements. The CRDA would oversee all functions of the district and will make changes to attract new businesses and attractions. New construction would be ambitious and may resort to eminent domain.

What year were the boundaries for the state-run tourism district finally set?

What were the three major things that the district would include?

The district would include heavier police presence, as well as beautification and infrastructure improvements

Who would oversee all functions of the new district?

The CRDA

Who would make the changes within the district to attract new businesses and attractions?

The CRDA

What two qualities were mentioned in regards to new construction?

would be ambitious and may resort to eminent domain


The tourism district would comprise several key areas in the city; the Marina District, Ducktown, Chelsea, South Inlet, Bader Field, and Gardner's Basin. Also included are 10 roadways that lead into the district, including several in the city's northern end, or North Beach. Gardner's Basin, which is home to the Atlantic City Aquarium, was initially left out of the tourism district, while a residential neighborhood in the Chelsea section was removed from the final boundaries, owing to complaints from the city. Also, the inclusion of Bader Field in the district was controversial and received much scrutiny from mayor Lorenzo Langford, who cast the lone "no" vote on the creation of the district citing its inclusion.

How many roadways will be included in the district?

What place is home to the Atlantic City Aquarium?

Gardner's Basin

What place was originally left off of the tourism district?

Gardner's Basin

Where was the residential neighborhood that was removed from the final boundaries of the district?

Chelsea

Who cast the lone "no" vote on the creation of the district citing Bader Field's inclusion?

mayor Lorenzo Langford


Atlantic City is considered as the "Gambling Capital of the East Coast," and currently has eight large casinos and several smaller ones. In 2011, New Jersey's casinos employed approximately 33,000 employees, had 28.5 million visitors, made $3.3 billion in gaming revenue, and paid $278 million in taxes. They are regulated by the New Jersey Casino Control Commission and the New Jersey Division of Gaming Enforcement.

What is Atlantic City known for?

Gambling Capital of the East Coast

How many large casinos are located in Atlantic City?

eight

Approximately how many people did New Jersey casinos employ in 2011?

Approximately how many people visited New Jersey's casinos in 2011?

28.5 million

What two entities regulate New Jersey's casino?

New Jersey Casino Control Commission and the New Jersey Division of Gaming Enforcement


In the wake of the United States' economic downturn and the legalization of gambling in adjacent and nearby states (including Delaware, Maryland, New York, and Pennsylvania), four casino closures took place in 2014: the Atlantic Club on January 13; the Showboat on August 31; the Revel, which was Atlantic City's second-newest casino, on September 2; and Trump Plaza, which originally opened in 1984, and was the poorest performing casino in the city, on September 16.

How many casino closures took place in Atlantic City in 2014?

four

What was the name of the poorest performing casino in the city that ultimately closed in 2014?

Trump Plaza

What year did Trump Plaza originally open?

What was the name of Atlantic City's second-newest casino that ultimately closed in 2014?

Revel

What was the name of the first casino to close in 2014?

Atlantic Club


Executives at Trump Entertainment Resorts, whose sole remaining property will be the Trump Taj Mahal, said in 2013 that they were considering the option of selling the Taj and winding down and exiting the gaming and hotel business.

What is the sole remaining property owned by Trump Entertainment Group?

Trump Taj Mahal

What did Trump Entertainment Group say they were considering doing with the Trump Taj Mahal?

selling

In what year did executives at Trump Entertainment Group say they were considering selling the Taj?

Why did executives say they were considering selling the Taj?

winding down and exiting the gaming and hotel business

Who spoke for the Trump Entertainment Group in regards to the Taj and what might be done in the future?

Executives


Caesars Entertainment executives have been reconsidering the future of their three remaining Atlantic City properties (Bally's, Caesars and Harrah's), in the wake of a Chapter 11 bankruptcy filing by the company's casino operating unit in January 2015.

How many remaining properties belong to Caesars Entertainment?

three

What are the names of the three remaining Caesars Entertainment properties?

Bally's, Caesars and Harrah's

What type of bankruptcy did Caesars Entertainment file for?

Chapter 11

What year did Caesars Entertainment file for bankruptcy?

Which unit of Caesars Entertainment filed for bankruptcy in 2015?

casino operating unit


Boardwalk Hall, formally known as the "Historic Atlantic City Convention Hall", is an arena in Atlantic City along the boardwalk. Boardwalk Hall was Atlantic City's primary convention center until the opening of the Atlantic City Convention Center in 1997. The Atlantic City Convention Center includes 500,000 sq ft (46,000 m2) of showroom space, 5 exhibit halls, 45 meeting rooms with 109,000 sq ft (10,100 m2) of space, a garage with 1,400 parking spaces, and an adjacent Sheraton hotel. Both the Boardwalk Hall and Convention Center are operated by the Atlantic City Convention & Visitors Authority.

What was Boardwalk Hall formerly known as?

Historic Atlantic City Convention Hall

What is the Boardwalk Hall?

an arena

In what year did the newer Atlantic City Convention Center open?

How many sq ft of showroom space is included in the Atlantic City Convention Center?

500,000 sq ft

What hotel is adjacent to the Atlantic City Convention Center?

Sheraton hotel


Atlantic City (sometimes referred to as "Monopoly City") has become well-known over the years for its portrayal in the U.S. version of the popular board game, Monopoly, in which properties on the board are named after locations in and near Atlantic City. While the original incarnation of the game did not feature Atlantic City, it was in Indianapolis that Ruth Hoskins learned the game, and took it back to Atlantic City. After she arrived, Hoskins made a new board with Atlantic City street names, and taught it to a group of local Quakers.

What is Atlantic City sometimes referred to?

Monopoly City

The names of many properties near Atlantic City are used in which popular board game?

Monopoly

Who learned the game of Monopoly and took it to Atlantic City?

Ruth Hoskins

What location was originally featured in the  Monopoly game?

Indianapolis

Who did Ruth Hoskins teach the game of Monopoly to?

a group of local Quakers


Marvin Gardens, the leading yellow property on the board shown, is actually a misspelling of the original location name, "Marven Gardens". The misspelling was said to have been introduced by Charles Todd and passed on when his home-made Monopoly board was copied by Charles Darrow and thence Parker Brothers. It was not until 1995 that Parker Brothers acknowledged this mistake and formally apologized to the residents of Marven Gardens for the misspelling although the spelling error was not corrected.

What popular property in Monopoly was actually a misspelling?

Marvin Gardens

What is the name of the original property that Marvin Gardens takes its name from?

Marven Gardens

Whose game did Parker Brothers model the board game after?

Charles Darrow

In what year did Parker Brothers acknowledge and apologize for a spelling error in the game?

Who copied Charles Todd's Monopoly board?

Charles Darrow


Immunology is a branch of biomedical science that covers the study of immune systems in all organisms. It charts, measures, and contextualizes the: physiological functioning of the immune system in states of both health and diseases; malfunctions of the immune system in immunological disorders (such as autoimmune diseases, hypersensitivities, immune deficiency, and transplant rejection); the physical, chemical and physiological characteristics of the components of the immune system in vitro, in situ, and in vivo. Immunology has applications in numerous disciplines of medicine, particularly in the fields of organ transplantation, oncology, virology, bacteriology, parasitology, psychiatry, and dermatology.

In general, what does immunology study?

immune systems in all organisms

Immunology studies the functioning of the immune system in which two states of being?

both health and diseases

Name three types of immunological disorders?

autoimmune diseases, hypersensitivities, immune deficiency, and transplant rejection

Immunology studies the immune system in which three stages of existence?

in vitro, in situ, and in vivo

What disciplines in medicine have particularly strong immunology applications?

organ transplantation, oncology, virology, bacteriology, parasitology, psychiatry, and dermatology


Prior to the designation of immunity from the etymological root immunis, which is Latin for "exempt"; early physicians characterized organs that would later be proven as essential components of the immune system. The important lymphoid organs of the immune system are the thymus and bone marrow, and chief lymphatic tissues such as spleen, tonsils, lymph vessels, lymph nodes, adenoids, and liver. When health conditions worsen to emergency status, portions of immune system organs including the thymus, spleen, bone marrow, lymph nodes and other lymphatic tissues can be surgically excised for examination while patients are still alive.

The term immunology is derived from a Latin word that means what?

exempt

What are the major organs of the immune system?

thymus and bone marrow, and chief lymphatic tissues such as spleen, tonsils, lymph vessels, lymph nodes, adenoids, and liver

Who originally discovered these parts of the immune system?

early physicians

How do physicians study a patient's immune system organs in emergency situations?

surgically excised for examination while patients are still alive

Which portions of the immune system can be safely removed in these emergency cases?

thymus, spleen, bone marrow, lymph nodes and other lymphatic tissues


Many components of the immune system are typically cellular in nature and not associated with any specific organ; but rather are embedded or circulating in various tissues located throughout the body.

The structure of immune system components can be described as what?

typically cellular in nature

Are immune tissues typically fixed with specific organs usually?

not associated with any specific organ

What is one way the cellular structures of the immune system are housed in the body?

embedded

What is another way these tissues are housed within the body?

circulating


Classical immunology ties in with the fields of epidemiology and medicine. It studies the relationship between the body systems, pathogens, and immunity. The earliest written mention of immunity can be traced back to the plague of Athens in 430 BCE. Thucydides noted that people who had recovered from a previous bout of the disease could nurse the sick without contracting the illness a second time. Many other ancient societies have references to this phenomenon, but it was not until the 19th and 20th centuries before the concept developed into scientific theory.

Which two fields of study are associated with immunology?

epidemiology and medicine

Immunology studies how which three areas impact one another?

the body systems, pathogens, and immunity

When was the first written mention of immunity as it pertains to the body?

430 BCE

Which Greek historian made that notation?

Thucydides

When did immunology start to become codified as a scientific theory?

19th and 20th centuries


The study of the molecular and cellular components that comprise the immune system, including their function and interaction, is the central science of immunology. The immune system has been divided into a more primitive innate immune system and, in vertebrates, an acquired or adaptive immune system. The latter is further divided into humoral (or antibody) and cell-mediated components.

What is the basic, primitive part of the immune system known as?

innate immune system

Vertebrates also have what type of immune system component?

acquired or adaptive immune system

What is one type of adaptive immune system component?

humoral (or antibody)

Name the other type of adaptive immune system component?

cell-mediated

The total immune system is generally composed of what types of structures?

molecular and cellular components


The humoral (antibody) response is defined as the interaction between antibodies and antigens. Antibodies are specific proteins released from a certain class of immune cells known as B lymphocytes, while antigens are defined as anything that elicits the generation of antibodies ("anti"body "gen"erators). Immunology rests on an understanding of the properties of these two biological entities and the cellular response to both.

Humoral immunology involves the interaction of what two elements?

antibodies and antigens

What are antibodies comprised of?

specific proteins

What cells produce antibodies?

B lymphocytes

The term "antigen" is rooted in what two words?

"anti"body "gen"erators

Immunology is the study of what type of responses to antibodies and antigens?

cellular response


Immunological research continues to become more specialized, pursuing non-classical models of immunity and functions of cells, organs and systems not previously associated with the immune system (Yemeserach 2010).

In the field of immunology, what aspect is becoming more specialized?

research

What new areas are immunologists studying with more frequency?

non-classical models of immunity

The latest research into newer aspects of immunology is focused on what three elements of the body?

cells, organs and systems

These three elements of the body are of new interest for what reason?

not previously associated with the immune system


Clinical immunology is the study of diseases caused by disorders of the immune system (failure, aberrant action, and malignant growth of the cellular elements of the system). It also involves diseases of other systems, where immune reactions play a part in the pathology and clinical features.

The study of diseases caused by immune system disorders is called?

Clinical immunology

What are three problems of the immune system studied by clinical immunology?

failure, aberrant action, and malignant growth

Where can these three elements occur in the immune system?

cellular elements

What else does clinical immunology concern itself with?

diseases of other systems

Why does clinical immunology extend to those areas?

immune reactions play a part in the pathology and clinical features


Other immune system disorders include various hypersensitivities (such as in asthma and other allergies) that respond inappropriately to otherwise harmless compounds.

What is a type of immune system disorder?

hypersensitivities

What are some examples of hypersensitivities?

asthma and other allergies

What characterizes a hypersensitivity?

respond inappropriately to otherwise harmless compounds.


The most well-known disease that affects the immune system itself is AIDS, an immunodeficiency characterized by the suppression of CD4+ ("helper") T cells, dendritic cells and macrophages by the Human Immunodeficiency Virus (HIV).

What is the most famous immune system disease?

AIDS

What kind of disease is AIDS?

an immunodeficiency

Which types of cells are suppressed by AIDS?

CD4+ ("helper") T cells, dendritic cells and macrophages

What virus specifically suppresses those cells?

Human Immunodeficiency Virus (HIV)


The body’s capability to react to antigen depends on a person's age, antigen type, maternal factors and the area where the antigen is presented. Neonates are said to be in a state of physiological immunodeficiency, because both their innate and adaptive immunological responses are greatly suppressed. Once born, a child’s immune system responds favorably to protein antigens while not as well to glycoproteins and polysaccharides. In fact, many of the infections acquired by neonates are caused by low virulence organisms like Staphylococcus and Pseudomonas. In neonates, opsonic activity and the ability to activate the complement cascade is very limited. For example, the mean level of C3 in a newborn is approximately 65% of that found in the adult. Phagocytic activity is also greatly impaired in newborns. This is due to lower opsonic activity, as well as diminished up-regulation of integrin and selectin receptors, which limit the ability of neutrophils to interact with adhesion molecules in the endothelium. Their monocytes are slow and have a reduced ATP production, which also limits the newborn's phagocytic activity. Although, the number of total lymphocytes is significantly higher than in adults, the cellular and humoral immunity is also impaired. Antigen-presenting cells in newborns have a reduced capability to activate T cells. Also, T cells of a newborn proliferate poorly and produce very small amounts of cytokines like IL-2, IL-4, IL-5, IL-12, and IFN-g which limits their capacity to activate the humoral response as well as the phagocitic activity of macrophage. B cells develop early during gestation but are not fully active.

What are the four factors that determine how the body reacts to an antigen?

person's age, antigen type, maternal factors and the area

Why are newborns described as being physiologically immunodeficient?

both their innate and adaptive immunological responses are greatly suppressed

Newborns are particularly susceptible to infections caused by?

low virulence organisms like Staphylococcus and Pseudomonas

What activity is also greatly reduced in newborn infants?

phagocytic

Antigen cells in newborns are also struggle to do this?

activate T cells


Maternal factors also play a role in the body’s immune response. At birth, most of the immunoglobulin present is maternal IgG. Because IgM, IgD, IgE and IgA don’t cross the placenta, they are almost undetectable at birth. Some IgA is provided by breast milk. These passively-acquired antibodies can protect the newborn for up to 18 months, but their response is usually short-lived and of low affinity. These antibodies can also produce a negative response. If a child is exposed to the antibody for a particular antigen before being exposed to the antigen itself then the child will produce a dampened response. Passively acquired maternal antibodies can suppress the antibody response to active immunization. Similarly the response of T-cells to vaccination differs in children compared to adults, and vaccines that induce Th1 responses in adults do not readily elicit these same responses in neonates. Between six to nine months after birth, a child’s immune system begins to respond more strongly to glycoproteins, but there is usually no marked improvement in their response to polysaccharides until they are at least one year old. This can be the reason for distinct time frames found in vaccination schedules.

In babies, what is another element impacting immune response?

Maternal factors

Newborns can acquire antibodies from the mother through what means?

breast milk

For how long do these antibodies have an effect on infants?

up to 18 months

At 6 to 9 months, an infant's immune system begins to respond to which proteins?

glycoproteins

The difference in responses in infant immune systems is the cause of what?

distinct time frames found in vaccination schedules


During adolescence, the human body undergoes various physical, physiological and immunological changes triggered and mediated by hormones, of which the most significant in females is 17-β-oestradiol (an oestrogen) and, in males, is testosterone. Oestradiol usually begins to act around the age of 10 and testosterone some months later. There is evidence that these steroids act directly not only on the primary and secondary sexual characteristics but also have an effect on the development and regulation of the immune system, including an increased risk in developing pubescent and post-pubescent autoimmunity. There is also some evidence that cell surface receptors on B cells and macrophages may detect sex hormones in the system.

What is the primary trigger for immunological changes in teens?

hormones

What specific hormone catalyzes these changes in females?

17-β-oestradiol (an oestrogen)

Which specific hormone precipitates the change in immunology in males?

testosterone

Adolescent immunological changes can also result in what?

increased risk in developing pubescent and post-pubescent autoimmunity

Evidence suggests that receptors on B cells may do what?

detect sex hormones in the system


Immunology is strongly experimental in everyday practice but is also characterized by an ongoing theoretical attitude. Many theories have been suggested in immunology from the end of the nineteenth century up to the present time. The end of the 19th century and the beginning of the 20th century saw a battle between "cellular" and "humoral" theories of immunity. According to the cellular theory of immunity, represented in particular by Elie Metchnikoff, it was cells – more precisely, phagocytes – that were responsible for immune responses. In contrast, the humoral theory of immunity, held by Robert Koch and Emil von Behring, among others, stated that the active immune agents were soluble components (molecules) found in the organism’s “humors” rather than its cells.

The routine practice of immunology can best be characterized as?

strongly experimental

What are two opposing theories of early 20th century immunology?

"cellular" and "humoral"

Cellular immunology expressed the theory that what cells caused immune responses?

phagocytes

Humoral immunology theorized that the origin of the immune system lay in what?

soluble components (molecules)

Rather than cells, in humoral immunology where did the molecules that cause immune response reside?

the organism’s “humors”


In the mid-1950s, Frank Burnet, inspired by a suggestion made by Niels Jerne, formulated the clonal selection theory (CST) of immunity. On the basis of CST, Burnet developed a theory of how an immune response is triggered according to the self/nonself distinction: "self" constituents (constituents of the body) do not trigger destructive immune responses, while "nonself" entities (e.g., pathogens, an allograft) trigger a destructive immune response. The theory was later modified to reflect new discoveries regarding histocompatibility or the complex "two-signal" activation of T cells. The self/nonself theory of immunity and the self/nonself vocabulary have been criticized, but remain very influential.

What medical scientist first proposed the clonal selection theory of immunology?

Frank Burnet

What triggers an immune response according to CST?

self/nonself distinction

In CST, what triggers a destructive immune response?

"nonself" entities (e.g., pathogens, an allograft)

What property of T cells caused modification of CST?

the complex "two-signal" activation

When was clonal selection theory first proposed?

In the mid-1950s


Bioscience is the overall major in which undergraduate students who are interested in general well-being take in college. Immunology is a branch of bioscience for undergraduate programs but the major gets specified as students move on for graduate program in immunology. The aim of immunology is to study the health of humans and animals through effective yet consistent research, (AAAAI, 2013). The most important thing about being immunologists is the research because it is the biggest portion of their jobs.

What discipline can undergraduate students interested in general health study?

Bioscience

Immunology is a branch of what larger field of study?

bioscience

The goal of an immunologist is to study what beings?

humans and animals

The biggest part of an immunologist's job is what?

research

What two conditions apply to good immunological study?

effective yet consistent research


Most graduate immunology schools follow the AAI courses immunology which are offered throughout numerous schools in the United States. For example, in New York State, there are several universities that offer the AAI courses immunology: Albany Medical College, Cornell University, Icahn School of Medicine at Mount Sinai, New York University Langone Medical Center, University at Albany (SUNY), University at Buffalo (SUNY), University of Rochester Medical Center and Upstate Medical University (SUNY). The AAI immunology courses include an Introductory Course and an Advance Course. The Introductory Course is a course that gives students an overview of the basics of immunology.

Most graduate schools specializing in immunology follow what organization's parameters?

AAI courses

What is the name of the immunology school at Mount Sinai?

Icahn School of Medicine

AAI immunology courses include what two components?

Introductory Course and an Advance Course

What does the introductory AAI immunology course do?

gives students an overview of the basics of immunology

The Langone Medical Center is part of what college?

New York University


In addition, this Introductory Course gives students more information to complement general biology or science training. It also has two different parts: Part I is an introduction to the basic principles of immunology and Part II is a clinically-oriented lecture series. On the other hand, the Advanced Course is another course for those who are willing to expand or update their understanding of immunology. It is advised for students who want to attend the Advanced Course to have a background of the principles of immunology. Most schools require students to take electives in other to complete their degrees. A Master’s degree requires two years of study following the attainment of a bachelor's degree. For a doctoral programme it is required to take two additional years of study.

Part 1 of the AAI introductory immunology course is meant to be what?

an introduction to the basic principles of immunology

Part 2 of the AAI introductory immunology course revolves around what?

clinically-oriented lecture series

What pre-requisite should enrollees in the advanced immunology course have?

a background of the principles of immunology

How long does it typically take to earn a Master's degree?

two years of study

What program requires an additional two years of study?

a doctoral programme


MPEG-1 or MPEG-2 Audio Layer III, more commonly referred to as MP3, is an audio coding format for digital audio which uses a form of lossy data compression. It is a common audio format for consumer audio streaming or storage, as well as a de facto standard of digital audio compression for the transfer and playback of music on most digital audio players.

What is the common name for MPEG-2 Audio Layer III?

What kind of audio is the coding format for?

digital

Other than storage, what is the common audio format used for?

consumer audio streaming

What does MP3 use to format it's data?

lossy data compression

Where will MP3 files most commonly be found?

digital audio players


The use of lossy compression is designed to greatly reduce the amount of data required to represent the audio recording and still sound like a faithful reproduction of the original uncompressed audio for most listeners. An MP3 file that is created using the setting of 128 kbit/s will result in a file that is about 1/11 the size of the CD file created from the original audio source (44,100 samples per second × 16 bits per sample × 2 channels = 1,411,200 bit/s; MP3 compressed at 128 kbit/s: 128,000 bit/s [1 k = 1,000, not 1024, because it is a bit rate]. Ratio: 1,411,200/128,000 = 11.025). An MP3 file can also be constructed at higher or lower bit rates, with higher or lower resulting quality.

What is the main goal aside from reducing the amount of data required to store the audio?

sound like a faithful reproduction

What kind of compression is used?

created

If a file is created using 128 kbit/s, what size is the file going to be compared to a CD?

How many total bit/s would a CD have?

How many total bit/s would an MP3 compressed at 128 kbit/s have?


The compression works by reducing the accuracy of certain parts of a sound that are considered to be beyond the auditory resolution ability of most people. This method is commonly referred to as perceptual coding. It uses psychoacoustic models to discard or reduce precision of components less audible to human hearing, and then records the remaining information in an efficient manner.

What does the compression target in the song?

accuracy

The targetting focuses on what aspect that is beyond the ability of most people?

auditory resolution

What is this method commonly referred to as?

perceptual coding

What kind of model is used in this kind of compression?

psychoacoustic

These models ensure that the precision is reduced for the components that are what to human hearing?

less audible


MP3 was designed by the Moving Picture Experts Group (MPEG) as part of its MPEG-1 standard and later extended in the MPEG-2 standard. The first subgroup for audio was formed by several teams of engineers at Fraunhofer IIS, University of Hannover, AT&T-Bell Labs, Thomson-Brandt, CCETT, and others. MPEG-1 Audio (MPEG-1 Part 3), which included MPEG-1 Audio Layer I, II and III was approved as a committee draft of ISO/IEC standard in 1991, finalised in 1992 and published in 1993 (ISO/IEC 11172-3:1993). Backwards compatible MPEG-2 Audio (MPEG-2 Part 3) with additional bit rates and sample rates was published in 1995 (ISO/IEC 13818-3:1995).

Who designed MP3?

Moving Picture Experts Group

What was the first standard that this group had?

The first standard later developed into which standard?

When was the draft passed to have MPEG-1 Audio approved as a standard?

When was MPEG-2 Audio finally published?


The MP3 lossy audio data compression algorithm takes advantage of a perceptual limitation of human hearing called auditory masking. In 1894, the American physicist Alfred M. Mayer reported that a tone could be rendered inaudible by another tone of lower frequency. In 1959, Richard Ehmer described a complete set of auditory curves regarding this phenomenon. Ernst Terhardt et al. created an algorithm describing auditory masking with high accuracy. This work added to a variety of reports from authors dating back to Fletcher, and to the work that initially determined critical ratios and critical bandwidths.

What does the MP3 compression take advantage of?

perceptual limitation

What is the limitation in human hearing referred to as?

auditory masking

Who was the physicist to report that a tone could be rendered inaudible.

Alfred M. Mayer

When were audio curves described by Richard Ehmer?

The initial work was aimed at determining critical ratios and what else?

critical bandwidths


The psychoacoustic masking codec was first proposed in 1979, apparently independently, by Manfred R. Schroeder, et al. from Bell Telephone Laboratories, Inc. in Murray Hill, NJ, and M. A. Krasner both in the United States. Krasner was the first to publish and to produce hardware for speech (not usable as music bit compression), but the publication of his results as a relatively obscure Lincoln Laboratory Technical Report did not immediately influence the mainstream of psychoacoustic codec development. Manfred Schroeder was already a well-known and revered figure in the worldwide community of acoustical and electrical engineers, but his paper was not much noticed, since it described negative results due to the particular nature of speech and the linear predictive coding (LPC) gain present in speech. Both Krasner and Schroeder built upon the work performed by Eberhard F. Zwicker in the areas of tuning and masking of critical bands, that in turn built on the fundamental research in the area from Bell Labs of Harvey Fletcher and his collaborators. A wide variety of (mostly perceptual) audio compression algorithms were reported in IEEE's refereed Journal on Selected Areas in Communications. That journal reported in February 1988 on a wide range of established, working audio bit compression technologies, some of them using auditory masking as part of their fundamental design, and several showing real-time hardware implementations.

What was first proposed in 1979?

The psychoacoustic masking codec

Which country were the researchers located in?

United States

Who was the first to produce hardware for speech?

Krasner

What does LPC stand for?

linear predictive coding

What was reported in IEEE's Journal on Selected Areas in Communications?

audio compression algorithms


The immediate predecessors of MP3 were "Optimum Coding in the Frequency Domain" (OCF), and Perceptual Transform Coding (PXFM). These two codecs, along with block-switching contributions from Thomson-Brandt, were merged into a codec called ASPEC, which was submitted to MPEG, and which won the quality competition, but that was mistakenly rejected as too complex to implement. The first practical implementation of an audio perceptual coder (OCF) in hardware (Krasner's hardware was too cumbersome and slow for practical use), was an implementation of a psychoacoustic transform coder based on Motorola 56000 DSP chips.

What does OCF stand for?

Optimum Coding in the Frequency Domain

What does PXFM stand for?

Perceptual Transform Coding

What was the name of the codec that OCF, PFXM and other contributes merged into?

ASPEC

Which competition did ASPEC win?

quality

What was the first practical implementation based on?

Motorola 56000 DSP chips


As a doctoral student at Germany's University of Erlangen-Nuremberg, Karlheinz Brandenburg began working on digital music compression in the early 1980s, focusing on how people perceive music. He completed his doctoral work in 1989. MP3 is directly descended from OCF and PXFM, representing the outcome of the collaboration of Brandenburg—working as a postdoc at AT&T-Bell Labs with James D. Johnston ("JJ") of AT&T-Bell Labs—with the Fraunhofer Institut for Integrated Circuits, Erlangen, with relatively minor contributions from the MP2 branch of psychoacoustic sub-band coders. In 1990, Brandenburg became an assistant professor at Erlangen-Nuremberg. While there, he continued to work on music compression with scientists at the Fraunhofer Society (in 1993 he joined the staff of the Fraunhofer Institute).

What kind of student was Karlheinz Brandenburg?

doctoral

When did Karlheinz start working on digitmal music compression?

early 1980s

Where did Bradenburg become an assistant professor at?

Erlangen-Nuremberg

Who did Brandenburg work with in music compression?

Fraunhofer Society

When did Brandenburg join the Fraunhofen Institute?


The song "Tom's Diner" by Suzanne Vega was the first song used by Karlheinz Brandenburg to develop the MP3. Brandenburg adopted the song for testing purposes, listening to it again and again each time refining the scheme, making sure it did not adversely affect the subtlety of Vega's voice.

What was the name of the first song used to develop the MP3?

Tom's Diner

Who was the artist of the first song used?

Suzanne Vega

Who adjusted the song?

Karlheinz Brandenburg

The song was listened to multiple times to try and refine what?

scheme

What particular aspect of the artists voice was he trying to preserve?

subtlety


In 1991, there were only two proposals available that could be completely assessed for an MPEG audio standard: Musicam (Masking pattern adapted Universal Subband Integrated Coding And Multiplexing) and ASPEC (Adaptive Spectral Perceptual Entropy Coding). The Musicam technique, as proposed by Philips (the Netherlands), CCETT (France) and Institut für Rundfunktechnik (Germany) was chosen due to its simplicity and error robustness, as well as its low computational power associated with the encoding of high quality compressed audio. The Musicam format, based on sub-band coding, was the basis of the MPEG Audio compression format (sampling rates, structure of frames, headers, number of samples per frame).

How many proposals were available in 1991?

two

Other than ASPEC what was another proposal?

Musicam

The Musicam format was proposed by Philips, based in which country?

Netherlands

Which other quality alongside simplicty was key in selecting this proposal?

error robustness

What was the Musican format based on?

sub-band coding


Much of its technology and ideas were incorporated into the definition of ISO MPEG Audio Layer I and Layer II and the filter bank alone into Layer III (MP3) format as part of the computationally inefficient hybrid filter bank. Under the chairmanship of Professor Musmann (University of Hannover) the editing of the standard was made under the responsibilities of Leon van de Kerkhof (Layer I) and Gerhard Stoll (Layer II).

What was only incorporated into Layer III and not Layers I or II?

filter bank

Who was the chair that oversaw the editing of the standard?

Professor Musmann

Who's responsibility was it to edit the standard for Layer I?

Leon van de Kerkhof

Who's responsibility was it to edit the standard for Layer II?

Gerhard Stoll


ASPEC was the joint proposal of AT&T Bell Laboratories, Thomson Consumer Electronics, Fraunhofer Society and CNET. It provided the highest coding efficiency.

What was the name given to the proposal?

ASPEC

What did the joint proposal provide?

the highest coding efficiency

Other than Thomson Consumer Electronics, Fraunhofer Society and CNET, who else was a part of the joint proposal?

AT&T Bell Laboratories


A working group consisting of Leon van de Kerkhof (The Netherlands), Gerhard Stoll (Germany), Leonardo Chiariglione (Italy), Yves-François Dehery (France), Karlheinz Brandenburg (Germany) and James D. Johnston (USA) took ideas from ASPEC, integrated the filter bank from Layer 2, added some of their own ideas and created MP3, which was designed to achieve the same quality at 128 kbit/s as MP2 at 192 kbit/s.

What did the working group take ideas from?

ASPEC

What did the working group integrate their ideas with?

filter bank

Where was the filter bank taken from?

Layer 2

What did the working group eventually create?

What quality were they hoping to match at 128 kbit/s?

MP2 at 192 kbit/s


All algorithms for MPEG-1 Audio Layer I, II and III were approved in 1991 and finalized in 1992 as part of MPEG-1, the first standard suite by MPEG, which resulted in the international standard ISO/IEC 11172-3 (a.k.a. MPEG-1 Audio or MPEG-1 Part 3), published in 1993.

When were the algorithms approved?

When were the approved algorithms finalized?

What was the first started suite by MPEG?

What was the official name of the internation standard?

ISO/IEC 11172-3

When was the international standard published?


Further work on MPEG audio was finalized in 1994 as part of the second suite of MPEG standards, MPEG-2, more formally known as international standard ISO/IEC 13818-3 (a.k.a. MPEG-2 Part 3 or backwards compatible MPEG-2 Audio or MPEG-2 Audio BC), originally published in 1995. MPEG-2 Part 3 (ISO/IEC 13818-3) defined additional bit rates and sample rates for MPEG-1 Audio Layer I, II and III. The new sampling rates are exactly half that of those originally defined in MPEG-1 Audio. This reduction in sampling rate serves to cut the available frequency fidelity in half while likewise cutting the bitrate by 50%. MPEG-2 Part 3 also enhanced MPEG-1's audio by allowing the coding of audio programs with more than two channels, up to 5.1 multichannel.

Further work on MPEG was finalized as a part of which MPEG standard?

second suite

What was the official name of ISO/IEC 13818-3 better known as?

At what rate were the new sampling rates defined in comparison to MPEG-1 Audio?

half

Apart from cutting the frequency fidelity in half, what else was cut in half?

bitrate

Allowing the coding of audio programs with more than two channels was a major aspect of what?

MPEG-2 Part 3


An additional extension to MPEG-2 is named MPEG-2.5 audio, as MPEG-3 already had a different meaning. This extension was developed at Fraunhofer IIS, the registered MP3 patent holders. Like MPEG-2, MPEG-2.5 adds new sampling rates exactly half of that previously possible with MPEG-2. It thus widens the scope of MP3 to include human speech and other applications requiring only 25% of the frequency reproduction possible with MPEG-1. While not an ISO recognized standard, MPEG-2.5 is widely supported by both inexpensive and brand name digital audio players as well as computer software based MP3 encoders and decoders. A sample rate comparison between MPEG-1, 2 and 2.5 is given further down. MPEG-2.5 was not developed by MPEG and was never approved as an international standard. MPEG-2.5 is thus an unofficial or proprietary extension to the MP3 format.

As MPEG-3 had a different meaning, what was the name given to the extension of MPEG-2?

MPEG-2.5 audio

Where was this extension developed?

Fraunhofer IIS

The new sampling rates widened the scope of MP3 to be able to include what?

human speech

What is not an ISO recognized standard?

As MPEG-2.5 is unofficial, it is considered what kind of extension to the MP3 format?

proprietary


Compression efficiency of encoders is typically defined by the bit rate, because compression ratio depends on the bit depth and sampling rate of the input signal. Nevertheless, compression ratios are often published. They may use the Compact Disc (CD) parameters as references (44.1 kHz, 2 channels at 16 bits per channel or 2×16 bit), or sometimes the Digital Audio Tape (DAT) SP parameters (48 kHz, 2×16 bit). Compression ratios with this latter reference are higher, which demonstrates the problem with use of the term compression ratio for lossy encoders.

What defines the compression efficiency of encoders?

bit rate

Compression ratio depends on the sample rate and bit depth of which signal?

input

What does CD stand for?

Compact Disc

What can CD parameters be used as references for?

compression ratios

Other than CD parameters, what else can be used as parameter references?

Digital Audio Tape (DAT) SP


Karlheinz Brandenburg used a CD recording of Suzanne Vega's song "Tom's Diner" to assess and refine the MP3 compression algorithm. This song was chosen because of its nearly monophonic nature and wide spectral content, making it easier to hear imperfections in the compression format during playbacks. Some refer to Suzanne Vega as "The mother of MP3". This particular track has an interesting property in that the two channels are almost, but not completely, the same, leading to a case where Binaural Masking Level Depression causes spatial unmasking of noise artifacts unless the encoder properly recognizes the situation and applies corrections similar to those detailed in the MPEG-2 AAC psychoacoustic model. Some more critical audio excerpts (glockenspiel, triangle, accordion, etc.) were taken from the EBU V3/SQAM reference compact disc and have been used by professional sound engineers to assess the subjective quality of the MPEG Audio formats.

What type of recording did Brandenburg use?

CD

What did Brandenburg use the recording to refine?

the MP3 compression algorithm

What word describes the nature of the song used?

monophonic

As a result of her song being used, Suzanne Vega is sometimes referred to as what?

The mother of MP3

Excerpts were taken from which reference compact disc to assess the subjective quality of the MPEG audio formats?

EBU V3/SQAM


A reference simulation software implementation, written in the C language and later known as ISO 11172-5, was developed (in 1991–1996) by the members of the ISO MPEG Audio committee in order to produce bit compliant MPEG Audio files (Layer 1, Layer 2, Layer 3). It was approved as a committee draft of ISO/IEC technical report in March 1994 and printed as document CD 11172-5 in April 1994. It was approved as a draft technical report (DTR/DIS) in November 1994, finalized in 1996 and published as international standard ISO/IEC TR 11172-5:1998 in 1998. The reference software in C language was later published as a freely available ISO standard. Working in non-real time on a number of operating systems, it was able to demonstrate the first real time hardware decoding (DSP based) of compressed audio. Some other real time implementation of MPEG Audio encoders were available for the purpose of digital broadcasting (radio DAB, television DVB) towards consumer receivers and set top boxes.

Which language was the reference simulation software written in?

C

Who developed the reference simulation software?

the ISO MPEG Audio committee

When was the reference software approved?

March 1994

When did the reference software become an international standard?

What could the reference software demonstrate?

real time hardware decoding


On 7 July 1994, the Fraunhofer Society released the first software MP3 encoder called l3enc. The filename extension .mp3 was chosen by the Fraunhofer team on 14 July 1995 (previously, the files had been named .bit). With the first real-time software MP3 player WinPlay3 (released 9 September 1995) many people were able to encode and play back MP3 files on their PCs. Because of the relatively small hard drives back in that time (~ 500–1000 MB) lossy compression was essential to store non-instrument based (see tracker and MIDI) music for playback on computer.

When was the first software MP3 encoder released?

7 July 1994

What was the name of the first software MP3 encoder?

What was the filename extension?

What was the name of the first real-time software MP3 player?

What was the average high end hard drive size?

1000 MB


As sound scholar Jonathan Sterne notes, "An Australian hacker acquired l3enc using a stolen credit card. The hacker then reverse-engineered the software, wrote a new user interface, and redistributed it for free, naming it "thank you Fraunhofer"".

What was Jonathan Sterne's profession?

sound scholar

Which nationality was the hacker who acquired I3enc?

Australian

What did the hacker use to acquire the software?

stolen credit card

The hacker re-wrote which element of the program?

user interface

How much did the new released program by the hacker cost?

free


In the second half of '90s, MP3 files began to spread on the Internet. The popularity of MP3s began to rise rapidly with the advent of Nullsoft's audio player Winamp, released in 1997. In 1998, the first portable solid state digital audio player MPMan, developed by SaeHan Information Systems which is headquartered in Seoul, South Korea, was released and the Rio PMP300 was sold afterwards in 1998, despite legal suppression efforts by the RIAA.

Where did MP3s begin to spread?

the Internet

Which audio player was released in 1997?

Winamp

Who released the audio player?

Nullsoft

What was the name of the first portable solid state digital audio player?

MPMan

In which country was the first portable audio player developed?

South Korea


In November 1997, the website mp3.com was offering thousands of MP3s created by independent artists for free. The small size of MP3 files enabled widespread peer-to-peer file sharing of music ripped from CDs, which would have previously been nearly impossible. The first large peer-to-peer filesharing network, Napster, was launched in 1999.

Which website offered MP3s for free?

How many MP3s were offered for free by the website?

thousands

What kind of file sharing became popular due to the file sizes of MP3s?

peer-to-peer

How did people come into possession of MP3s?

ripped from CDs

Which network was the first large peer to peer file sharing network?

Napster


The ease of creating and sharing MP3s resulted in widespread copyright infringement. Major record companies argued that this free sharing of music reduced sales, and called it "music piracy". They reacted by pursuing lawsuits against Napster (which was eventually shut down and later sold) and against individual users who engaged in file sharing.

What kind of infringement resulted from sharing MP3s?

copyright

What name did the record companies associate with MP3 file sharing?

music piracy

Who was the target of the record companies?

Napster

What happened to Napster?

shut down and later sold


Unauthorized MP3 file sharing continues on next-generation peer-to-peer networks. Some authorized services, such as Beatport, Bleep, Juno Records, eMusic, Zune Marketplace, Walmart.com, Rhapsody, the recording industry approved re-incarnation of Napster, and Amazon.com sell unrestricted music in the MP3 format.

What kind of MP3 file sharing continues on?

Unauthorized

Beatport, Bleep and Juno records are examples of what kind of service?

authorized

What kind of music is sold by these companies?

unrestricted

Which format is used by the companies that sell the music legally?


An MP3 file is made up of MP3 frames, which consist of a header and a data block. This sequence of frames is called an elementary stream. Due to the "byte reservoir", frames are not independent items and cannot usually be extracted on arbitrary frame boundaries. The MP3 Data blocks contain the (compressed) audio information in terms of frequencies and amplitudes. The diagram shows that the MP3 Header consists of a sync word, which is used to identify the beginning of a valid frame. This is followed by a bit indicating that this is the MPEG standard and two bits that indicate that layer 3 is used; hence MPEG-1 Audio Layer 3 or MP3. After this, the values will differ, depending on the MP3 file. ISO/IEC 11172-3 defines the range of values for each section of the header along with the specification of the header. Most MP3 files today contain ID3 metadata, which precedes or follows the MP3 frames, as noted in the diagram.

A header and data block together make up what?

MP3 frames

What is a sequence of MP3 frames called?

elementary stream

What is used to identify the begining of a valid frame of an MP3 header?

dard

How many bits are needed to indicate that layer 3 is used?

two

MP3 files today contain what kind of metadeta?


The MPEG-1 standard does not include a precise specification for an MP3 encoder, but does provide example psychoacoustic models, rate loop, and the like in the non-normative part of the original standard. At present, these suggested implementations are quite dated. Implementers of the standard were supposed to devise their own algorithms suitable for removing parts of the information from the audio input. As a result, there are many different MP3 encoders available, each producing files of differing quality. Comparisons are widely available, so it is easy for a prospective user of an encoder to research the best choice. An encoder that is proficient at encoding at higher bit rates (such as LAME) is not necessarily as good at lower bit rates.

Which standard does not include a specification for an MP3 encoder?

Example psychoacoustic models and rate loops can be foundin which part of the original standard?

non-normative

What were implementers of the standard supposed to devise?

their own algorithms

It is easy for a prospective user of an encoder to research the best choice because of what factor?

Comparisons are widely available

An encoder that is proficient at encoding at higher bit rates might be worse at what?

lower bit rates


During encoding, 576 time-domain samples are taken and are transformed to 576 frequency-domain samples.[clarification needed] If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)

How many domain samples are taken during encoding?

Domain samples are transformed into what?

frequency-domain samples

When are 192 samples taken instead of 576?

there is a transient

When 192 samples are taken instead of 576, it is done in an effort to limit what?

temporal spread

What accompanies a transient?

quantization noise


Due to the tree structure of the filter bank, pre-echo problems are made worse, as the combined impulse response of the two filter banks does not, and cannot, provide an optimum solution in time/frequency resolution. Additionally, the combining of the two filter banks' outputs creates aliasing problems that must be handled partially by the "aliasing compensation" stage; however, that creates excess energy to be coded in the frequency domain, thereby decreasing coding efficiency.[citation needed]

What kind of structure does a filter bank have?

tree

Due to a specific kind of structure, what kind of problems are made worse?

pre-echo problems

What kind of resolution are the filter banks unable to provide an optimal solution for?

time/frequency

Combining two filter banks' outputs creates what kind of problem?

aliasing

The need to code excess energy in the frequency domain decreases what kind of efficiency?

coding


Decoding, on the other hand, is carefully defined in the standard. Most decoders are "bitstream compliant", which means that the decompressed output that they produce from a given MP3 file will be the same, within a specified degree of rounding tolerance, as the output specified mathematically in the ISO/IEC high standard document (ISO/IEC 11172-3). Therefore, comparison of decoders is usually based on how computationally efficient they are (i.e., how much memory or CPU time they use in the decoding process).

What is carefully defined in the standard?

Decoding

What are most decoders?

bitstream compliant

The ISO/IEC high standard document states that the decompressed output produced from a given MP3 file will be the same within what standards?

specified degree of rounding tolerance

Decoders are usually compared by examining which factor?

computationally efficient

The efficiency of decoders is examined by seeing how much memory and what other process they use in the decoding process?

CPU time


Encoder / decoder overall delay is not defined, which means there is no official provision for gapless playback. However, some encoders such as LAME can attach additional metadata that will allow players that can handle it to deliver seamless playback.

What is there no official provision for?

gapless playback

What is an example of an encoder that can attach additional metadeta?

LAME

Adding additional metadata allows players to handle gapless playback and deliver what?

seamless playback

For encoders and decoders, what is not defined?

overall delay


When performing lossy audio encoding, such as creating an MP3 file, there is a trade-off between the amount of space used and the sound quality of the result. Typically, the creator is allowed to set a bit rate, which specifies how many kilobits the file may use per second of audio. The higher the bit rate, the larger the compressed file will be, and, generally, the closer it will sound to the original file.

A typical trade off when creating an MP3 file is between the amount of space used and what other factor?

sound quality of the result

What would an example of lossy audio encoding be?

creating an MP3 file

Who gets to set the bit rate for an MP3 file?

the creator

What does the bit rate of the file actually mean?

how many kilobits the file may use per second of audio

If the bit rate is higher, the size of the compressed file will be what?

larger


With too low a bit rate, compression artifacts (i.e., sounds that were not present in the original recording) may be audible in the reproduction. Some audio is hard to compress because of its randomness and sharp attacks. When this type of audio is compressed, artifacts such as ringing or pre-echo are usually heard. A sample of applause compressed with a relatively low bit rate provides a good example of compression artifacts.

If the bit rate is too low, what might be audible in the reproduction?

compression artifacts

Sounds that were not in the original recording are referred to as what?

compression artifacts

Randomness and sharp attacks are two reasons that may make it harder to to do what to an audio file?

compress

Other than pre - echo, what is another example of what can happen when audio is compressed?

ringing

What kind of sample can display a good example of compression artifacts?

A sample of applause


Besides the bit rate of an encoded piece of audio, the quality of MP3 files also depends on the quality of the encoder itself, and the difficulty of the signal being encoded. As the MP3 standard allows quite a bit of freedom with encoding algorithms, different encoders may feature quite different quality, even with identical bit rates. As an example, in a public listening test featuring two different MP3 encoders at about 128 kbit/s, one scored 3.66 on a 1–5 scale, while the other scored only 2.22.

Other than the bit rate and the difficulty of the signal, what can also affect the quality of an MP3 file?

quality of the encoder

The MP3 standard allows encoders to have a lot of freedom with which aspect of encoding?

encoding algorithms

As a result of the freedom, different encoders can result in different quality even if which aspect of the file is the same?

bit rates

An example shown has a low range quality score of what value?

To compare qualities, sound files are evaluated on a scale that ranges from 1 to what?


The simplest type of MP3 file uses one bit rate for the entire file: this is known as Constant Bit Rate (CBR) encoding. Using a constant bit rate makes encoding simpler and faster. However, it is also possible to create files where the bit rate changes throughout the file. These are known as Variable Bit Rate (VBR) files. The idea behind this is that, in any piece of audio, some parts will be much easier to compress, such as silence or music containing only a few instruments, while others will be more difficult to compress. So, the overall quality of the file may be increased by using a lower bit rate for the less complex passages and a higher one for the more complex parts. With some encoders, it is possible to specify a given quality, and the encoder will vary the bit rate accordingly. Users who know a particular "quality setting" that is transparent to their ears can use this value when encoding all of their music, and generally speaking not need to worry about performing personal listening tests on each piece of music to determine the correct bit rate.

How many bit rates does the simplest type of MP3 file use?

one

What does CBR stand for?

Constant Bit Rate

What does VBR stand for?

Variable Bit Rate

Aside from silence, which sections of music highlight parts that are easier to compress?

music containing only a few instruments

What value do users need to know when encoding their music to help avoid them having to do tests on each piece of music?

quality setting


Perceived quality can be influenced by listening environment (ambient noise), listener attention, and listener training and in most cases by listener audio equipment (such as sound cards, speakers and headphones).

A listening environment is also know by which term?

ambient noise

Other than speakers and headphones, what other piece of equipment affects the listener's perceived quality?

sound cards

Listening environment, listener attention, listener training and listener audio equipment can all affect what kind of quality?

Perceived quality


A test given to new students by Stanford University Music Professor Jonathan Berger showed that student preference for MP3-quality music has risen each year. Berger said the students seem to prefer the 'sizzle' sounds that MP3s bring to music.

Who gave students a test to determine their preferences?

Music Professor Jonathan Berger

Where was a test performed to collect data on student preference for MP3 quality?

Stanford University

Data showed that students' preference for MP3 quality music followed which trend?

risen each year

What kind of sound did students seem to prefer?

sizzle


An in-depth study of MP3 audio quality, sound artist and composer Ryan Maguire's project "The Ghost in the MP3" isolates the sounds lost during MP3 compression. In 2015, he released the track "moDernisT" (an anagram of "Tom's Diner"), composed exclusively from the sounds deleted during MP3 compression of the song "Tom's Diner", the track originally used in the formulation of the MP3 standard. A detailed account of the techniques used to isolate the sounds deleted during MP3 compression, along with the conceptual motivation for the project, was published in the 2014 Proceedings of the International Computer Music Conference.

What is the name of the study done by composer Ryan Maguire?

The Ghost in the MP3

What did the study aim to isolate?

sounds lost during MP3 compression

What is the track "moDernisT" an anagram of?

Tom's Diner

Where was an account of the study published?

International Computer Music Conference

Which year was the study published?


Several bit rates are specified in the MPEG-1 Audio Layer III standard: 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 kbit/s, with available sampling frequencies of 32, 44.1 and 48 kHz. MPEG-2 Audio Layer III allows bit rates of 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 kbit/s with sampling frequencies of 16, 22.05 and 24 kHz. MPEG-2.5 Audio Layer III is restricted to bit rates of 8, 16, 24, 32, 40, 48, 56 and 64 kbit/s with sampling frequencies of 8, 11.025, and 12 kHz.[citation needed] Because of the Nyquist–Shannon sampling theorem, frequency reproduction is always strictly less than half of the sampling frequency, and imperfect filters requires a larger margin for error (noise level versus sharpness of filter), so 8 kHz sampling rate limits the maximum frequency to 4 kHz, while 48 kHz maximum sampling rate limits an MP3 to 24 kHz sound reproduction.

What is the name of the sampling theorem?

Nyquist–Shannon

In relation to the sampling frequency, the frequency reproduction is strictly how much less?

less than half

What kind of filter requires a larger margin for error?

imperfect filters

Having an 8 kHz sampling rate would limit the maximum frequency to how much?

4 kHz

A sound reproduction of 24 kHz would represent which value of a maximum sampling rate?


A sample rate of 44.1 kHz is almost always used, because this is also used for CD audio, the main source used for creating MP3 files. A greater variety of bit rates are used on the Internet. The rate of 128 kbit/s is commonly used, at a compression ratio of 11:1, offering adequate audio quality in a relatively small space. As Internet bandwidth availability and hard drive sizes have increased, higher bit rates up to 320 kbit/s are widespread.

What sampling rate is used for CD audio?

44.1 kHz

What is the main source used for creating MP3 files?

CD audio

Where can one find a greater variety of bit rates?

the Internet

The common bit rate on the internet is 128 kbit/s using which compression ratio?

As technology advances, what is another higher bit rate that is beginning to spread?

320 kbit/s


Uncompressed audio as stored on an audio-CD has a bit rate of 1,411.2 kbit/s, (16 bit/sample × 44100 samples/second × 2 channels / 1000 bits/kilobit), so the bitrates 128, 160 and 192 kbit/s represent compression ratios of approximately 11:1, 9:1 and 7:1 respectively.

What is stored on an audio-CD that has a bit rate of 1,411.2 kbit/s?

Uncompressed audio

What does a bit rate of 128 represent in terms of compression ratio?

What would a bit rate of 160 correspond to in terms of compression ratio?

What would a bit rate of 192 kbit/s have for a compression ratio?


Non-standard bit rates up to 640 kbit/s can be achieved with the LAME encoder and the freeformat option, although few MP3 players can play those files. According to the ISO standard, decoders are only required to be able to decode streams up to 320 kbit/s.

What is the highest bit rate the LAME encoder allows?

640 kbit/s

The LAME encoder allows bit rates that are what?

Non-standard

Even though few MP3 players can play it, LAME also offers which option?

freeformat

The ISO standard dictates that decoders only need to be able to decode streams that have how high of a bit rate?


Early MPEG Layer III encoders used what is now called Constant Bit Rate (CBR). The software was only able to use a uniform bitrate on all frames in an MP3 file. Later more sophisticated MP3 encoders were able to use the bit reservoir to target an average bit rate selecting the encoding rate for each frame based on the complexity of the sound in that portion of the recording.

What does the term CBR mean?

Constant Bit Rate

Which early MPEG layer used CBR?

Layer III

The early software was restricted to which kind of bitrate?

uniform

What did more sophisticated MP3 encoders use to target an average bit rate?

bit reservoir

What did encoders base the encoding rate for each frame on?

the complexity of the sound