snd_envy24{,ht} recording support?
Lev Serebryakov
lev at FreeBSD.org
Thu Mar 21 00:25:09 UTC 2013
Hello, Yamagi.
You wrote 20 марта 2013 г., 11:52:07:
YB> On Tue, 19 Mar 2013 15:19:59 +0100
YB> David Demelier <demelier.david at gmail.com> wrote:
YB> just listen to music, there's the possibility to send a digital signal
YB> by spdif to an external a/d-converter, etc... The need for high end add
Unfortunately, here is NOT MoBo with proper S/PDIF support. ALL of
them uses Realtek chips which doesn't support proper 44.1Khz
sampling rate, has "hardcoded" DSP settinga and is equipped only
with 48Khz (or 96/192) crystal, so try to output CD sound via S/PDIF
on any modern MoBo will lead to re-sampling, processinh and/or bad
synthesized carrier frequency (which is fatal for S/PDIF).
Naturally, unpacked WAV file, sent via on-board S/PDIF optical link to
professional card arrives as completely different beast.
You need good USB DAC (with "asynchronous" mode, which is rare, and
I don't know, is it supported by FreeBSD USB stack at all) or some
additional two-crystal card to connect good DAC to computer via coax
or optical S/PDIF.
And, ironically enough, cheapest way to do so is to buy some
Chinese PCI or PCIe card, based on envy24[ht], which could be bought
for $15-$20. It will be equipped with very bad DAC and analog path
will be crap, but it will have "true", transparent, bit-correct
S/PDIF.
--
// Black Lion AKA Lev Serebryakov <lev at FreeBSD.org>
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