F.A.Q. - Some Terms & Definitions:
Lossy or Lossless?
What is lossless material?
Lossless is a form of compression that allows the original file to be compressed and uncompressed whilst retaining all of the original data. No data is lost. In terms of music this means that the Lossless files that you download retain all of the quality of the original recording resulting in the best possible sound quality. Lossy compression (mp3 files etc.) is a form of compression that permanently compresses the original file resulting (depending on bitrate) in considerable amounts of data being lost. This loss of data reduces the overall quality of the file but offers smaller file sizes in return. A standard Lossless recording averages at about 800MB but the same show in mp3 can be as little as 100mb.
What is the difference between lossless and lossy?
The answer to that is quite simple. Lossless audio (like Microsoft's WAV format), is audio that is either totally uncompressed, or is compressed (like FLAC or SHN) in a way that no quality is permanently lost, and when decompressed is exactly the same as before it was compressed. Lossy audio however (like mp3), is audio that is digitally compressed, and data is actually lost. The programs used to compress to these formats will decide what bits of the audio it doesn't feel is needed and discards it PERMANENTLY. It can NOT be recovered, unlike lossless formats.
Why is lossy audio like MP3 and WMA bad?
Many people believe that mp3 is "CD quality audio at around a tenth of the file size". But this CANNOT BE TRUE. If 90% of the original CD audio file is gone, there MUST be a loss in quality. Surely even an eight year old child could work that out. What mp3 supposedly does is get rid of the parts of the sound that are in the high end of the frequency range, that it doesn't think the human ear could hear. This is true to some extent, but as a whole the sound is now missing something. From a distance it may sound the same, but close up or through headphones you can tell the difference, it is more hollow and lacking somewhat.
So, you give me all this facts, but prove it!
The best way to show this is to use a program to analyze two versions of an audio file, one in lossless WAV format and another in lossy format like mp3. For this i am going to use a program called AnalFreq. First of all I'll just tell you that the average human beings hearing range is roughly from 20Hz to just over 20kHz. Bear that in mind when looking at the following information.
The file I will be analyzing will be a song, from a random CD. So first i ripped the File from my CD using Exact Audio Copy (EAC) to a lossless WAV file. The size of this file was 26.4mb. So now I'll open that WAV in AnalFreq. This is what we see after analysis:
Pretty different huh? Notice how the frequency completely drops off at just 14kHz. So much for your CD quality audio. This is what mp3 suffers from, the complete lack of upper end frequencies, and contrary to what some may say, frequencies which the human ear CAN hear. So now do you see why mp3 and other similar files are deemed lossy and inappropriate for trading?
But what about FLAC and SHN, they're compressed aren't they?
Yes, you're quite right, the audio codecs FLAC and SHN, along with the less used APE are all compressed just like mp3. However there is a BIG difference between them. Where as mp3 compresses files in a lossy way, removing audio data FOREVER, these don't. They are compressed in a lossless way. When a WAV is compressed to FLAC, no data is actually discarded permanently like mp3, it is done in a way simply to squash the file down to be then decompressed.
If you decompress FLAC, SHN or APE back to WAV or AIFF, the resulting file, unlike the mp3, will be IDENTICAL in size and quality to the original WAV or AIFF that you compressed in the first place. Therefore these are deemed LOSSLESS. The advantage of these formats is that they can cut the size of the WAV significantly, making it a lot quicker to download, and taking up less space on you Hard Drive.
So to clarify,
# If the frequency goes up to around around 22kHz, your recording is LOSSLESS, and is fine.
# If the frequency cuts of at around 14khz, your recording is LOSSY, likely mp3 sourced.
There is a couple of things in the middle though.
If your recording cuts of at around 20.5kHz (or sometimes less), then it is most likely sourced from a TV or Radio broadcast. This is perfectly acceptable to trade.
Also, some recordings may be sourced from a 32kHz DAT tape, which can produce results similar to mp3, so be careful and look at the linage of the source for a DAT step.
THERE IS ABSOLUTELY NO REASON WHY YOU SHOULD TRADE AND COLLECT SHOWS IN MP3. IT IS AN INFERIOR FORMAT AND SHOULD BE AVOIDED.
Please Note: A frequency analysis is not the only way to determine whether audio files have undergone a lossy compression process. Nor is it definitive of losslessness...
(Thanks to Brian Pasley)
File Formats:
.wav
Short for WAVeform Audio Format, it is normally used in an uncompressed format on the Windows platform. This raw audio format, which was developed jointly by IBM and Microsoft, stores audio data in blocks. On the digital music scene, it's usefulness has diminished over time with the development of better lossless audio formats, such as FLAC or SHN. It is a standard that will probably be used for some time yet due to it's widespread use in professional music recording and is still a very popular format for audio applications.
.mp3
(MPEG-1 Audio Layer-3). Mp3 is popular compressed audio file format that helped popularize digital music downloads beginning in the late 1990s. Mp3 files are typically about 1/10 the size of uncompressed WAV file, but maintain nearly the same CD-quality sound. Because of their small size and good fidelity, Mp3 files have become a popular way to store music, but it is a lossy compression scheme. This means when music is converted into the Mp3 format, a certain amount of data is lost and cannot be recovered!
.flac
(Free Lossless Audio Codec). It is a royalty-free codec used to compress CD audio files to at least 50% of their original size (2:1 ratio). Unlike Mp3, which provides much greater compression but eliminates content, FLAC restores the music to the original PCM 44kHz, 16-bit audio stream of CD audio. Although a 2:1 ratio is not extraordinary, the same disk holds twice as much music while maintaining the original quality. For example, if CDs are ripped to MP3s, the Mp3s cannot be converted to take advantage of better quality using a different compression method, and if converted, they may very well lose some quality. However, FLAC files could be decompressed to the original format and compressed with the new method.
.shn
(Shorten) is an audio compression scheme written by Tony Robinson of SoftSound that can compact wav files without subtracting out any frequencies. It's lossless - everything in the original wav is there, so that full quality is maintained. For many traders of live music, Shorten files (shns) therefore have an undisputed advantage over lossy Mp3-format files. A shn file made from a wav is quite a bit larger than the corresponding mp3, with a size perhaps ~50-70% of the orginal wav.
.md5
Plain text files with checksum informations. The checksum strings inside are like 32-character ID numbers for each file, used to check the integrity of the file and to "fingerprint" it. People create md5s at the same time they create the files. The files are typically named by band, show date, and often disc, such as oasis2000-04-20d1.md5. Within the md5 file there should be a separate line for each file. Use the handy md5 files to verify the integrity of your files. Why check md5s? Since the files are really big, they can get corrupted more easily than smaller files during data transfer or even during CD burning. A file copied without glitches should always be identical to it's parent file and have the same checksum "fingerprint". If the file was changed through corruption, it will no longer match it's original fingerprint and the check will fail. If the md5 check fails, redownload the file (or even try "resume" in your ftp program), or recopy the file from your data disc and try again. If it fails repeatedly, contact your host operator or trading partner - his own copy may be defective. If there are no md5s to check, you take your chances with errors.
Recordings:
Soundboard (SBD)
Recorded from the band's mixing board. As good as can be and with the only audience sound coming from leakage or the band's mikes. Often grouped in for Studio recordings, rare soundboard tapes, radio or outtakes. Officially released live albums are always soundboard. FM's are a soundboard source but the audio range is more limited and can come close to resembling a mp3 frequency.
Digital Audio Tape (DAT)
A digital audience recording, typically made in a designated taper's section by a fan (and recorded with a dat recording (digital audio tape) recorder. Depending on how these are recorded and how noisy the adjacent audience members are these can be as good as a soundboard recording (but with more audience noise inbetween songs) or bad if adjacent audience noise overwhelms the band performance.
Mini Disc (MD)
An audience recording using a MiniDisc player. These are the lowest price available recording devices. While these are genrally frowned upon by hardcore tapers as they do lower the sound range and requiring flipping during a long concert, they can get achieve some great recordings with great mics and with low adjacent audience participation.
ALD Recordings
Bootleggers can request an ALD (Assisted Listening Device) headset at an arena concert (required by law for hearing impaired fans), which provides a high-quality feed of a live show using a low-level FM frequency broadcast inside a facility. Bootleggers will tape this headset feed, giving the bootleg not usual problems like random crowd noise or distortion.
IEM Recordings
In Ear Monitors are devices used by performers to hear a mix of microphones and/or instrument pickups that are on the stage. They are often custom fitted to the individuals ears and provide a high level of noise reduction from stage noise.
Matrix Recordings
A matrix recording is a new recording consisting of different tapes from the same show. An example can be that you have an audience and IEM recording (both have their own (dis)advantages) and you want to mix them in one recording, that would be a matrix.
Pro-Shot Video
A television appearance recorded to vhs or dvd recorder, can be later transfered to dvd. A digital capture will be the best resolution, followed by a master generation high recording quality. Pro-shots are the equivalent of video soundboard recordings and will feature multiple cameras.
Mini DV
Used to film from the audience members perspective. These are the wave of the future as the camcorders are much smaller than ever before, they are cheaper, better, and easier to share via recordable dvd's. Sound can be a lesser quality but improvements are occuring with better mics in cameras, external mics with better audio sound, and mixes from FM or great AUD audio sources into the finished product.
Trading:
FTP
(File Transfer Protocol) is the simplest way to exchange files between computers on the Internet. Using FTP you can download or upload files to a private or public server. You need to logon to an FTP server with a name and password. It is a way of trading but can be difficult to find and support for trading shows online. You also need software to get to files via ftp. FTP is not generally used by the Oasis community but may be for individual online traders.
Usergroups
Usergroups are one of the oldest ways to get infos and download shows. A user group is a set of people who have similar interests, goals or concerns. They often have Websites that each member can visit on a regular basis to stay informed.
Torrents
Torrents are the newest way of sharing. One person starts a torrent and then people begin downloading from the original seeder. As you are downloading you also share with people below you with less of the show. It's a great way to spread a show and almost always guarantee a completion in a given evening. However, torrents last only a short period of time so it's very possible to miss out on shows.
Trading via Mail
Send First: Often used when an unestablished trader trades with an established trader. The person who does the contacting sends to the person first and once the shows arrive the established trader sends their shows to them.
Send Simulataneously: Both traders arrange to send their shows to each other at the same time.
B&P's: A way to get started by contacting an established trader and sending them blanks (at 1:1 or 2:1 ratio) for the shows they want. Also enclosed is a self-addressed envelope with postage to get it back to the sender. A rare occurance but still a nice way to get started.
Permissions:
Audience Recordings
Audience recordings are the major source of getting great shows. Since there are large costs associated with getting equipment, purchasing tickets, sneaking in equipment, remaining perfectly still, and ensuring the recording goes off without a hitch, it's important to support your local tapers. Even shows taped off the radio onto dats, md, or casette or transfer from tv to dvd exist thanks to someone taking the time to record a show. Please maintain these guidelines for ensuring a steady flow of shows to the community.
Unlisted Shows
Many tapers trade amongst themselves and these recordings are often asked not to leak out. These may include the best quality shows or shows that have never circulated from a certain city. Be aware that these recordings exist, that they are not supposed to be circulated amongst everyone, and they are part of how the community works. If you want to get the best and rarest shows available than you will probably want to tape be a part of the taper community.
Restricted Shows
These are shows that are available to the trading community but have parameters set up by the taper on how he would like them traded. This generally reflects that they don't want the shows spread through the internet (via hub or torrent), or that they would like permisison before any trade takes place (so they can track who has recordings). These shows are harder to get without a large collection or knowing how to track these recordings down.
Circulated Shows
These shows are traded via mail but also online through ftp, hubs or bit torrents. They are generally pretty common when widely circulated and may make it harder to trade with other traders but easier with people who collect other bands.
