On 12/2/2011 4:53 PM, Bill de Carle wrote:
My question is this:
In a practical situation with low QRN/QRM, would going to a
24-bit ADC soundcard result in an ability to detect a weak LF signal
that would not show up on a Spectrum Lab display computed from 16-bit values?
In theory, of course
yes. But you English-speaking
people have a very pragmatical saying :
"The proof of the pudding is in the eating..." :-)
It would be interesting to see weak signal receptions done both with
a 16-bit sound card,
and 24-bit one, under the same conditions, and compare them.
But there is one thing that must be kept always in mind.
Medium-to-high class 24-bit sound cards,
like e.g. the Delta 44, have a nominal amplitude resolution
of 24 bits. Tests done by Leif
SM5BSZ (if I recall correctly) showed that only 19 to 20 of those 24
bits are meaningful....
the rest is just noise.
Perhaps, but this is just speculation on my side, going to a bit
more professional 24-bit card,
like the Lynx2 or the E-MU 1212M, could gain another bit (maybe two)
of resolution....
Both those cards use what is considered the best audio codec chip,
the AK-5394A.
These are the specs of the E-MU card : (I am not a reseller of
them... :-) )
![http://dl.dropbox.com/u/15089947/emu1212mspec.gif]()
73 Alberto I2PHD
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