In a message dated 97-10-25 21:06:26 EDT, James Bowman wrote:

> Does anybody know how to do this?
>  How much audio can you get in 6000 bits?
>
>  Thanks.
>  J.
>

A lot depends on how you encode the data. A few years ago, I developed a
device that played short advertisements interspersed with music on a
telephone system whenever the phone was on hold. I stored the audio on eprom
cartridges and played the sound back by reading the compressed data with a
PIC, decompressing the data, and sending it to an a/d converter. The most
difficult part of the project was developing the compression scheme. There
was a tradeoff between good compression and good sound quality. The
compression scheme I finally went with involved analyzing sequential sections
of the audio for frequency content and dynamic range. I then used one of
several compression schemes for that section of the recording. In segments
that were fairly quiet I obtained very high compression while segments with a
lot of information were able to maintain high quality. The compression was
done on a PC compatible computer so the PIC was only responsible for
decompression which is much simpler than compression.

Bob