[sdiy] 5mV of noise ...

[Magnus Danielson]

From: "Bert Schiettecatte" <bert at percussa.com>
Subject: [sdiy] 5mV of noise ...
Date: Thu, 16 Jun 2005 23:15:53 +0200
Message-ID: <004701c572b8$941266b0$4101a8c0 at laptop>

> Hi all,
> 
> I have a silly question so don't shoot me. I'm still learning on analog
> stuff.. I have been breadboarding some audio circuitry and I measured
> between 4mV and 5mV of noise. Exactly how bad is this? Of course I could
> convert this into dB I suppose but even then I'm not sure how bad this
> is once you start passing sound through it. 

If your referens level is 775 mV, a noise of 5 mV(RMS) equals -43.8 dBm. This
is bad. That's only 43.8 dB of dynamics. OK, let's say you have 6 dB of head-
room but that only gives you 50 dB of dynamics. OK, if you like the dynamics
of tape-recorders it may fit your needs, but you can do alot better.

Cheers,
Magnus