Gonzalo wrote:

>     Well, I guess ISD chip records some noise, is it possible to eliminate
> it? maybe while recording... any tricks?

Once the board layout is good (nice separation between ana and dig, plenty
of bypassing, fat short traces where needed, etc per datasheets), using the
sound recorded with no mic is a good basis for comparison.  Then for a
second comparison make one no-mic recording with a battery and the other
with a line supply.  Changing AGC and playing with other values can also be
instructive.  But if you mean below the noise threshold of the system's
design...?

Bruce Cannon
Style Management Systems
http://siliconcrucible.com
(510) 787-6870
1228 Ceres ST Crockett CA 94525

Remember: electronics is changing your world...for good!

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