12 Dec
2004
12 Dec
'04
6:31 p.m.
Thanks for all today lessons!
Andrew
======= On Monday 13 December 2004 00:18, Fons Adriaensen wrote: =======
On Sun, Dec 12, 2004 at 09:03:32PM +0300, Andrew Gaydenko wrote:
Probably, the last questions today :-)
1. What is the meaning of the "10 * log10 (Fsample / 2)" part?
It's just the frequency range expressed in dB.
No = noise density = power per Hertz.
No * frequency_range = noise_power.
In dB, the multiply becomes an addition.
And since the maximum signal level is O dB, SNR = -noise_power.
2. When noise spectrum is approximately flat - is
there
a common correlation with A-weighted value (say, "about 10db")?
I have no exact value at hand, but yes, it will be something like
10 dB. Most manufacturers of sound cards give the A-weighted figure
(if anything at all) -- it looks better :-)
--
FA