MP3 (MPEG-1 audio Layer-3) 12/15/200
Overview: MP3 compressed music requires about 64Mb per 1hr. music
when compressed at 128K bps
compared to 650Mb for a standard CD with up to 74 minutes of music in WAV format.
Sharing music over the Internet has become popular and controversial;
You've probably heard about Napster, a web site which facilitates peer to peer
sharing of MP3 files.
Higher quality MP3 can be recorded at 192 - 320 Kbs.
Although this is much lower than the 1.4 Mbs for CDs, it sound good because
it compresses by discarding signals
that are barely noticeable to the human ear.
WMA (Windows Media Audio) format
is better for low bit rate encoding 16 - 64 Kbs, while MP3 is better for high bit rate
128 - 320 encoding.
Playback: MP3 compressed music can be played in several ways
Sources: You can either download music from the Internet or convert
your CD's to MP3. The latter requires special software on your PC
or a special CD player with conversion software built in.
The process requires several steps:
- on your PC using audio software such as Windows Media Player, QuickTime,
Winamp, RealPlayer, MusicMatch Jukebox, ...
- MP3 players the size a PDA ($200-$300) with 64 to 128M memory or
memory cards. You download music from your PC to the MP3 player via a USB or parallel interface.
64Mb memmory cards which work with some players
are available for about $150. Others use PocketZip [40Mb] or
MicroDrive disks [340Mb]).
- from CD's you create yourself with a writable CD writer and playback
with a special CD player.
There is specalized software for each process as well
The MP3 players usually connect to the USB port and have software for downloading
music from your PC.
- Ripping or digital audio extraction (DAE)(A bit-to-bit copy of the CD to computer hard disk)
Some software also copies song titles from the CDDB (CD database) on the CD.
A new PC with a high speed CD drive can rip a CD in 10 min.
Audio extraction through an microphone input to a sound card in a PC,
causes a significant drop in quality depending on the overall quality of the sound card.
- Encoding (wav files compressed to MP3 files)
You can encode at 128 or 160 Kbps for CD Quality (160 Kbs takes 30% more space, 1.15 MB/min)
or 64 Kbps for FM Quality.
Better recorders use variable bit-rate (VBR) encoding to adjust the
bit rate with a range depending on the complexity of the music.
- Playing (convert back to analog and send to sound card/speakers)
or download to a MP3
MP3 Site List at Yahoo
MP3 Site List at Good
MP3 at Lycos
MP3 Direct Download
Software - Players, Converters
Combination Sftwr. Ripper, encoder, and player
Reviews at ZDNet
Reviews at C Net
Mac Compatible Players: Diamond Rio PMP500, Nomad IIMG, I-Jam IJ-50
Audio - Video
Digital Audio (MP3) players under Products.
MP3 Now Site
MP3 page at about.com.
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