42
File Types and Storage
Making MP3 Files
Encoding
Making MP3 files involves using an encoder, and you can find them readily available
from the web. A couple that we have seen work well are
Audio Catalyst,
which is
available from
Xing Technology Corporation
(www.xintech.com), and
Music
Match JukeBox
available from
MusicMatch
(www.musicmatch.com)
.
Fraunhofer
IIS Institute in partnership with Thomson Multimedia own patents on tools that make
MP3-compliant bitstreams. Due to the fact that Fraunhofer charges a royalty from
each encoder distributor, it is sometimes difficult to find a freeware MP3 encoder.
But at the time of this printing, MusicMatch (mentioned above) does have a free
encoding utility in their Jukebox. Audio Catalyst is a lot more flexible than
MusicMatch Jukebox, but you’ll need to purchase it. You can also purchase a MP3
encoder plug-in for Microsoft Windows Media Player running on Windows XP. Go
to the
Tools
window in Windows Media Player for details.
Quality
The 16-bit linear PCM format, like a WAV file, can provide higher quality audio
playback than the MP3 format, but at the same time it consumes about ten times as
much storage space per minute. This is based on a 128Kbps sample rate.
You CAN
get better than CD quality audio in an MP3 file
– you just have to make sure your
source material is better than CD quality to begin with, and you have to encode it at a
high bitrate, such as 160Kbps.
Below is a useful comparison of bitrates, quality, and file size. All you will need to
do is choose the bitrate at which you want the file encoded, which best fits in with
your storage space requirements. The most common, and recommended bitrates are
bolded.
Bitrate
(Kbps)
Quality
File Size (1
Minute file)
80
FM radio quality.
.594Mbytes
96
Near CD quality
.712Mbytes
128
Close enough to CD Quality most listeners can’t tell a difference
0.950Mbytes
160
Better than CD quality (at 48KHz) – good for high end stereos
1.19Mbytes
320
Best quality, good for archiving, but takes up lots of memory
2.38Mbytes
Compact Flash Media
Содержание AM-4
Страница 1: ...AM 4 Digital Audio Machine Hardware and Software Reference Manual ...
Страница 2: ...ii Welcome PLACE HOLDER FOR THE BACK OF THE FRONT COVER DO NOT PRINT ...
Страница 3: ...Welcome iii Digital Audio Machine User s Guide Alcorn McBride Inc ...
Страница 6: ......
Страница 10: ...4 Quick Start Guide ...
Страница 32: ...26 Controlling the AM 4 ...
Страница 58: ...52 GPS Operation GPS Operation ...
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Страница 71: ...Mechanical Information 65 Mechanical Information Mechanical Dimensions Surface Mounting ...
Страница 74: ...68 Mechanical Information Rack Mount Kit 2 Unit Part Number 302 100704 ...