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Old May 23rd 04, 07:06 PM posted to rec.audio.tech,rec.audio.misc,rec.audio.pro,uk.rec.audio,comp.sys.mac.misc
philicorda
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Default Digital audio stream terms?

On Sun, 23 May 2004 09:14:58 -0700, DaveC wrote:

iTunes displays data about each audio file. This data includes "sample rate"
and "bit rate". (These are MP3 audio files, converted from CD.)

Sample rates include 44.1 and 22.05. These I understand. Bit rates include
128Kbps and 56Kbps. If these are not streamed sources, but just digitized
files, why is there a bit rate associated with them. It seems just a logical
to display a bit rate for a MS Word file...


Bit rates for MP3s are a measure of the filesize/quality trade off.
The lower the bit-rate, the smaller the resulting file, and the lower the
quality.
Bit rate is independent of sample rate.
So, you can encode a 44.1k mp3 at 128kbps, or 256kbps or whatever.
The sample rate remains the same, but the fidelity is less.

They are not 'just digitised files', they are MP3s, which bear very little
relation to the original uncompressed CD data. The data MP3s contain is
more like a description of the sound, rather than an analog of it.
The description can be less exact (Less kbps) but still be recognisable.

Confused (still)...