sample rates in audio

[Stephen Barncard]

Actually you could halve that sample rate to 11 K and still have good 
intelligibility. Using the Nyquest theorem, the highest frequency you 
can record at a given sample rate is approximately less than half its 
sample rate. AM broadcast stations cut off at 5khz, which can be 
handled easily by the 11k sample rate.

This is not 11 k bits per second, like in MP3s, but a full parallel 
16 bits at 11k and without compression, will have no artifacts, just 
bandwidth reduction - i.e. less high end.

sqb


>
>OK, yes, it works... but  one must stick with the default codec 
>"none" ... any attempt to set it to ulaw with the USB mic doesn't 
>work... and touching the input setting can also be a problem (i.e. 
>"dflt" is what we want.... nothing else)
>
>But anyway, it doesn't seem to matter too muich. For voice  I'm 
>getting small file sizes at 16 bit, 22.01kHz. (8 bit introduces to 
>much hiss and pops.) Setting the record format to "wave" and the 
>file extension to ".wav" means it boots on both platforms which is 
>great... WMP  on Windows and QT on the Mac.
>
>[ if you want  quality -- giant files...
>   set the recordsamplesize to 128.21
>   set the recordrate  to 44.1
>]
>

-- 
stephen barncard
s a n  f r a n c i s c o
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