Question: What does VBR stand for?
Answer: Variable Bit Rate

Question: Aside from silence, which sections of music highlight parts that are easier to compress?
Answer: music containing only a few instruments

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

Question: A listening environment is also know by which term?
Answer: ambient noise

Question: Other than speakers and headphones, what other piece of equipment affects the listener's perceived quality?
Answer: sound cards

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

Question: Who gave students a test to determine their preferences?
Answer: Music Professor Jonathan Berger

Question: Where was a test performed to collect data on student preference for MP3 quality?
Answer: Stanford University

Question: Data showed that students' preference for MP3 quality music followed which trend?
Answer: risen each year

Question: What kind of sound did students seem to prefer?
Answer: sizzle

Question: What is the name of the study done by composer Ryan Maguire?
Answer: The Ghost in the MP3

Question: What did the study aim to isolate?
Answer: sounds lost during MP3 compression

Question: What is the track "moDernisT" an anagram of?
Answer: Tom's Diner

Question: Where was an account of the study published?
Answer: International Computer Music Conference

Question: Which year was the study published?
Answer: 2014

Question: What is the name of the sampling theorem?
Answer: Nyquist–Shannon

Question: In relation to the sampling frequency, the frequency reproduction is strictly how much less?
Answer: less than half

Question: Having an 8 kHz sampling rate would limit the maximum frequency to how much?
Answer: 4 kHz

Question: What kind of filter requires a larger margin for error?
Answer: imperfect filters

Question: A sound reproduction of 24 kHz would represent which value of a maximum sampling rate?
Answer: 48

Question: What sampling rate is used for CD audio?
Answer: 44.1 kHz

Question: What is the main source used for creating MP3 files?
Answer: CD audio

Question: Where can one find a greater variety of bit rates?
Answer: the Internet

Question: The common bit rate on the internet is 128 kbit/s using which compression ratio?
Answer: 11:1

Question: As technology advances, what is another higher bit rate that is beginning to spread?
Answer: 320 kbit/s

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

Question: What does a bit rate of 128 represent in terms of compression ratio?
Answer: 11:1

Question: What would a bit rate of 160 correspond to in terms of compression ratio?
Answer: 9:1

Question: What would a bit rate of 192 kbit/s have for a compression ratio?
Answer: 7:1

Question: The LAME encoder allows bit rates that are what?
Answer: Non-standard

Question: Even though few MP3 players can play it, LAME also offers which option?
Answer: freeformat

Question: What is the highest bit rate the LAME encoder allows?
Answer: 640 kbit/s

Question: The ISO standard dictates that decoders only need to be able to decode streams that have how high of a bit rate?
Answer: 320

Question: What does the term CBR mean?
Answer: Constant Bit Rate

Question: Which early MPEG layer used CBR?
Answer: Layer III

Question: The early software was restricted to which kind of bitrate?
Answer: uniform

Question: What did more sophisticated MP3 encoders use to target an average bit rate?
Answer: bit reservoir

Question: What did encoders base the encoding rate for each frame on?
Answer: the complexity of the sound

Question: What kind of audio can a sophisticated MP3 encoder produce?
Answer: variable bitrate audio

Question: Which type of decoder must support bitrate switching on a per-frame basis?
Answer: layer III

Question: What do encoders use when the goal is to achieve a fixed level of quality?
Answer: VBR

Question: Using VBR instead of a constant bit rate encoding makes which part of encoding less predictable?
Answer: final file size

Question: An average bit rate is used when who choses an average value for the encoder to use?
Answer: the user

Question: A partially full frame's ability to have part of the next frame's audio data is referred to as what?
Answer: bit reservoir

Question: What kind of audio is required to use a bit reservoir?
Answer: Layer III

Question: What is a possible result of handling the bit reservoir?
Answer: encoding delay

Question: A bit reservoir allows for what kind of changes in effective bit rate?
Answer: temporary

Question: A large benefit of a bit reservoir is that you can use it even while encoding what kind of stream?
Answer: constant bitrate

Question: What can scale factor band 21 be shortened to?
Answer: sfb21

Question: What is the maximum frequency that scale factor band 21 can go up to?
Answer: 16 kHz

Question: The encoder has to choose between less acurate representation in band 21 or which factor in all bands below band 21?
Answer: less efficient storage

Question: What does less efficient storage result in for VBR encoding?
Answer: wasted bitrate

Question: What is a section of a file that contains metadeta referred to as?
Answer: tag

Question: What else can metadeta contain other than the title, artist or track  number?
Answer: album

Question: What do MP3 standards not define?
Answer: tag formats for MP3 files

Question: What would be needed to support metadata and obviate the need for tags?
Answer: a standard container format

Question: Other than the ID3v1, which similar standard format for tag exists?
Answer: ID3v2

Question: What is the most recently introduced standard for tag formatting?
Answer: APEv2

Question: What is the second place in a file that tags are normally stored, with the first being at the beginning?
Answer: end

Question: What is important to note about where the tags are stored?
Answer: separate from the actual MP3 frame data

Question: If the MP3 decoders do not extract information from the tags, what do they do to them?
Answer: treat them as ignorable, non-MP3 junk data

Question: What is the name given to the standard for measure and storing the loudness of an MP3 file?
Answer: ReplayGain

Question: What is measuring and storing loudness of an MP3 file also known as?
Answer: audio normalization

Question: What does the standard ReplayGain allow a player to automatically adjust?
Answer: the overall playback volume

Question: What program can be used to modify files based on ReplayGain measurements?
Answer: MP3Gain

Question: MP3Gain is important because it allows players without what capability to have adjusted playback?
Answer: ReplayGain capability

Question: Where is the basic MP3 decoding and technology patent free?
Answer: European Union

Question: What happened to the patents that caused them to be patent-free?
Answer: expired

Question: When will the technology be patent - free in the United States?
Answer: 31 December 2017

Question: Between which years did most of the MP3 patents in the US expire?
Answer: 2007 and 2015

Question: What has many organizations claiming ownership of patents related to aspects of MP3 led to?
Answer: legal threats

Question: Legal threats and confusion made it difficult to ensure what about patents regarding MP3 products?
Answer: which patents must be licensed

Question: What was the danger of not correctly patenting products?
Answer: patent infringement

Question: At what stage of the technology were these problems prevalent?
Answer: early stages

Question: What became publicly available on 6 December 1991?
Answer: MPEG-1 standard

Question: When can patents not be filed in most countries?
Answer: after prior art has been made public

Question: How long does it take for patents to expire after being filed?
Answer: 20 years