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MP3 is also called MPG3, MPG-3, MPG Level 3, MPG Level III, MPEG 3, etc. I have also seen mention of MPEG1 Level 3 which appears to be the same as MP3 from its description.
MP3 uses the same type of highly efficient and extremely clever fractal-based algorithms for compression as JPG does for photographs. Just as the JPG algorithms were designed specifically to compress photographs efficiently, so the MP3 algorithms were designed specifically to compress sound and music efficiently.
Like JPG, MP3 is a slightly lossy format, meaning that the final sound is not quite identical to the source. However, the degradation occurs in a very controllable manner and so can easily be kept to a level below that discernible to the listener. As with JPG, there is no loss when copying MP3 files, only when creating them.
What is the difference between an MP3 file and a conventional WAV file?
Conventional WAV files are not compressed. For sound or music of any significant duration, WAV files are huge.
The size of a normal good quality WAV file is very roughly 10MB per minute of sound or music, whereas that of the equivalent MP3 file is very roughly 1MB per minute. In other words, the MP3 file is very roughly one tenth of the size of the equivalent WAV file, with no discernible difference in quality. However, the compression ratio does depend on the nature of the sound or music recorded in the file and therefore can differ.
The much smaller size of MP3 files makes it feasible to store them on the sizes of hard disks commonly found on modern PC's and to download them via the Internet within a reasonable time, even with a modem connection.
Why did you say conventional WAV file?
Because there are now two major types of WAV files:
All MP3 players suffer from break-ups - interruptions to their output when the PC is very busy, for example when loading another program from the hard disk.
One of the most popular MP3 players is Nullsoft's WinAmp (distribution file size 476KB). Of the MP3 players I have tried, I have found WinAmp by far the least susceptible to break-ups. The program has a vast array of configuration parameters, best left at their default values until you become familiar with the program's basic operation.
It is also possible to purchase standalone non-computer equipment capable of playing MP3.
There is at least one portable Walkman-like unit, employing ram as storage instead of disks or cassette tape. Presumably you connect the device to your PC and copy MP3 files from the computer's hard disk into the device's ram. Details of this player is available at the RioPort web site.
Empeg are in the process of producing a car MP3 player. It stores up to 7000 tracks on a 28GB hard disk and uses the Linux operating system. Tracks are downloaded onto the device's hard disk from your PC.
I do not know of any standalone MP3 players which use high density exchangeable disks such as Iomega Zip disks or CD-ROM's for storage but they might well exist. The latter is a particularly inviting concept since a single CD-ROM could hold about ten hours of high quality music in MP3 format. DVD disks could hold even more.
It is not possible to play computer CD-ROM's holding MP3 files in a conventional audio CD player, although such a capability seems an obvious possibility for audio CD players in the near future.
How would you advise configuring WinAmp?
This is obviously a matter of personal choice, but with a high resolution screen format I would advise trying the program's double-size option (OPTIONS | DOUBLE SIZE). The font size for the playlist is configured separately (OPTIONS | PREFERENCES | OPTIONS | PLAYLIST FONT SIZE) and can also be usefully increased from the default if you use a high screen resolution. I then place the main window and the equaliser side by side at the top of the screen with the playlist, extended to nearly the full screen width, underneath.
What is a WinAmp skin?
A WinAmp skin is an optional additional set of files which create an alternative user interface for WinAmp. Only the appearance such as the shape and colour of items (such as the various controls) is changed, not their position. Most skins seem to have a similar design style to that of pinball machines and amusement arcade video games, where garish colours and fancy shapes and fonts are used, making it very difficult to distinguish the controls. A few skins are available in which the controls are easily seen, for example Cold Fusion (distribution file size 100KB).
A large number of WinAmp skins, including Cold Fusion, can be downloaded from the WinAmp web site.
Do I need a WinAmp skin? What happens if I try to run WinAmp without a skin?
You do not need a skin in order to run WinAmp. WinAmp works perfectly without a skin - or rather, it works perfectly with the skin which it has by default when you install it. The default skin is reasonably clear and obvious.
However, skin files tend to be small and installing skins is a very simple operation, so you may wish to try a few as an experiment.
What is a WinAmp plug-in?
A WinAmp plug-in is an optional set of files which adds extra facilities to WinAmp. There are two main types of plug-in:
I would especially recommend the magnificent Geiss plug-in, available from WinAmp's web site. This plug-in produces a display on the whole screen, creating wonderful rapidly moving images which scroll, zoom, swirl and twist. This plug-in requires DirectX 6, a software package available from Microsoft's web site which allows programs running under Windows to rapidly access the screen, sound, joystick, etc. Many modern games programs install a version of DirectX, but perhaps not version 6 which is fairly recent. DirectX is upwardly compatible, in other words a program designed to work with a specific version of DirectX will also work with all later versions (but almost certainly not any earlier versions). DirectX 5 components had an internal version number of 4.05.00.0155 and DirectX 6 components have an internal version number of 4.06.00.0318. If you install a program which includes DirectX, be careful not to overwrite a later version of it with an earlier version.
A particularly useful I/O plug-in is Nullsoft's Crossfading Output, which fades from one track to the next. It is available from WinAmp's web site.
Plug-ins vary considerably in their complexity of installation, configuration and usage. Be sure to read any instructions which come with them, for example on their accompanying web pages or in README.TXT files. Some plug-ins provide very pleasing displays or useful effects and you may well wish to explore them.
What does an MMSYSTEM326 error indicate?
If an MP3 WAV file is played on a Windows 95 PC without the necessary codec, the file will not be played and an MMSYSTEM326 error will occur. You need to obtain and install the required codec - see the answer to the next question for details.
What do I need to play MP3 WAV files?
In order to play MP3 WAV files, you need a sound board and external speakers, any program capable of playing conventional WAV files, and also a suitable codec for playing MP3 compressed WAV files.
A suitable codec is available for downloading from the Fraunhofer web site or from the Sound America web site. The distribution file is L3CODECX.EXE (233KB). To install the codec, just run the distribution file. Installation is trivially simple. Installation adds "Fraunhofer IIS MPEG Layer-3 Codec (decode only)" to the list of codecs in CONTROL PANEL | MULTIMEDIA | ADVANCED | AUDIO COMPRESSION CODECS. After installation of this codec all programs capable of running conventional WAV files will be able to run MP3 WAV files as well as continuing to be able to play all the types of files they could previously play.
What do I need to create my own MP3 files?
To convert conventional WAV files to MP3 files you need an MP3 encoder program. A large number of these are available for downloading on various web sites.
The BladeEnc encoder, downloadable from mp3.com, works well. It is a DOS program. To see a list of the program's command line options, after installation just type in the program's name with no parameters or switches.
Because of the huge amount of processing required, encoders take longer than real-time to encode. In other words, a track lasting three and a half minutes might take more than seven minutes to encode on a 233MHz computer, although this time depends on the computer's processor clock speed and whether other programs are running at the same time. BladeEnc allows you to specify its priority. High priority settings will make encoding run faster but will seriously impinge on the speed of other programs being run at the same time. Low priority settings will allow other programs to operate at near-normal speed but making encoding take longer. BladeEnc allows a batch of files to be encoded automatically using a wildcard filespec such as *.wav, which is extremely useful.
It would appear that DOS MP3 encoders are much faster than those which run under Windows. A Windows encoder took fifty minutes to process a three and half minute track compared with about seven minutes for BladeEnc.
After testing the encoded MP3 files, be sure to archive (if necessary) and delete the corresponding WAV files from your hard disk, in order to reclaim huge amounts of space.
What do I need to copy tracks from an audio CD?
To copy tracks from an audio CD you need a CD Ripper program. A large number of these are available for downloading on a variety of web sites.
The WinDAC32 CD ripper, downloadable from mp3.com, works well.
Depending on the speed of your CD-ROM drive and your computer, CD Rippers can operate faster than real-time. For example, a track which normally lasts three and a half minutes might only take thirty seconds to be copied to your hard disk.
What are the stages involved in getting a track from an audio CD into an MP3 file and then playing it?
www.mpeg.org has an extension collection of technical information.
To attempt to find an MP3 copy of a specific track, in any search engine, try looking for:
+"artist name" +"title" +mp3
Don't expect to easily find all the tracks you are looking for. In my experience your chances of finding what you want are very remote but this probably depends on your musical tastes. Even if you find a site listed with the track you want, it may well no longer be operative. Many MP3 sites have short lifetimes.
Try the Lycos MP3 search engine.
Try the MP3Meta search engine.
Sound America has a huge collection of television themes, mostly in MP3 WAV format.
When downloading an MP3 file using a web browser, it is often necessary to right-click on the link and select SAVE from the resulting mini-menu, rather than left-click on the link.
Remember that even MP3 files are large by Internet standards, about 1MB per minute, so you may wish to select a time to download when your Internet usage costs and/or phone call costs are at a minimum (for example, maybe at the weekend).
What is a codec?
A codec is piece of software which contains a coder-decoder algorithm for sound. The coder is used when creating the sound file, the decoder when playing it. I believe that Windows 95 comes with some simple codecs installed by default; other more sophisticated and more modern codecs can be obtained and installed as desired. In particular, you need to install the appropriate codec in order to play MP3 WAV files. Sometimes you can only easily obtain one half, the coder or the decoder, but the file is still called a codec.
Most programs which involve the use of sound in any way, such as games, CD Rippers, MP3 Encoders and MP3 Players install any codecs that they require automatically without you needing to be concerned about them at all.
For the curious, a list of currently installed codecs can be found in CONTROL PANEL | MULTIMEDIA | ADVANCED | AUDIO COMPRESSION CODECS. I would caution against modifying anything in this area of Control Panel unless you are an expert.
What is PCM?
PCM is Pulse Code Modulation. The volume of the sound is sampled at regular intervals, extremely frequently - thousands of times per second. Each sample is converted into a binary number and that is stored in the file or transmitted. In order to play back the data, each binary number is converted to an analog voltage, at the same rate as was used during recording. I believe that PCM is the simplest, uncompressed method of holding sound information, as used in conventional WAV files.
What are "all-in-one" MP3 programs?
"All-in-one" MP3 programs combine the functions of a CD Ripper, an MP3 Encoder and an MP3 Player.
I've only tried one "all-in-one" MP3 program and compared to the combination of WinDAC, BladeEnc and WinAmp it was, in my humble opinion, awful. Other all-in-one MP3 programs may well be far better.
What is DAC?
DAC is short for Digital Audio Converter (i.e. a CD Ripper), or Digital Audio Conversion (i.e. the copying of tracks from an audio CD).
Most recently modified 3-Apr-99