[LAU] Sample rate vs. SNR

[Len Ovens]

Just looking through TI's ADCs 96k and up. Any on chip audio circuitry
(level controls etc.) seems to lower SNR (101 db typ.) which is no
surprise. But what I did find interesting is that even 96k and 192k
devices seem to optimized for 48k. So the spec of 112db SNR would be true
for 48k, but by the time it gets to 96k that is down 3db (noise floor up
3db) and at 192k... not even listed.

So 192k is snake oil anyway, I'm not concerned, though I will say the 192k
device has better performance at 48K, much smoother frequency response.

My question is about the 48k vs. 96k. 96k would allow lower latency and
better in band frequency response, but worse noise. Is it worth the extra
disk space and cpu load for recording? Or would it be better to record at
48K and use 96K for live use where latency is more important than noise
floor? What is the best SNR I am practically going to find from mic to
converter? Does it matter if the ADC is 101 db SNR or 112 db SNR?


-- 
Len Ovens
www.OvenWerks.net