I scanned the link you provided.
When a Virtual Cable is used in
a path containing another
audio device (a hardware device, a software device other than Virtual Cable
and even another Virtual Cable device),
clock
difference effect occurs. To minimize
it, change cable clock
correction
multiplier until cable internal clock speed becomes closest
to another
device clock.
...
VAC uses relatively
simple linear resampling
algorithm and does not use dithering or other advanced smoothing
features. Therefore, conversion results may sound worse than an
original signal. To prevent quality degradation, you need to pay
attention to a format matching. In an ideal case, all three
formats (the playback client's format, the cable format and the
recording client's format) are the same.
{^_^}
On 20210830 01:22:58, Conrad, PA5Y
wrote:
Hello where did you read that? I had always
assumed that it did and was rather better at it than VAC. I
am very interested to learn how this stuff works.
Conrad
I see, VMP does not even try to match
clocks dynamically. I guess its author figures that's a bear
and a half, too.
{o.o}
On 20210829 15:14:16, Conrad, PA5Y wrote:
That is the best-case scenario for
virtual soundcards, but it is dependent on the routing,
whether you are using MME, WDM/KS or ASIO . But virtual
soundcards have a buffer, to help with under runs or over
runs and therefore data may not arrive when expected. To
some extent there will be some sample shifting due to timing
errors. This means that degradation can occur.
But VMP handles all of this very well and
certainly produces the best results.
If you read this:
https://documentation.help/Virtual-Audio-Cable/advanced.htm
It is all explained, but you must read
the whole thing as well as some hyperlinked pages to get a
picture. I wish that I could find a better reference, there
is a lot that I don’t understand, and it really affects my
EME operating. If your signals are well above the noise
floor then this issues are a lot less important, or at least
that is what I observe.
Conrad
What if the soundcard is just a
virtual card.....and you have a handfull of them all
calculated from your main cpu clock...?!?
Am 29.08.2021 21:34 schrieb
"Conrad, PA5Y" <g0ruz@...>:
Exactly!
Conrad
Dream along with me.....
You'd think that, wouldn't you; but, only when
you figure crystals are all perfectly on
frequency including your sound card crystals....
{^_-}
On 20210829 09:30:34, Siegfried Jackstien
wrote:
Set all sampling rates to same setting
48000 then no resampling problems...
Am 29.08.2021 17:36 schrieb Gedas <w8bya@...>:
Hiya Conrad, long time. Thanks !
Gedas, W8BYA EN70JT
Gallery at http://w8bya.com (under repair)
Light travels faster than sound....
This is why some people appear bright until you hear them speak.
On 8/29/2021 7:11 AM, Conrad, PA5Y
wrote:
Voice Meter Potato (VMP) also
gets my vote. I use it for many
tasks including running
demodulated audio from SDRCv3 or
Linrad (for EME) to WSJT-X. I
always found Sample Rate
Conversion artefacts when using
VAC. It has a similar effect to
poor phase noise on weak signals
with up to 2dB degradation when
compared to a radio (K3S or
TS-890) and a soundcard. This does
not happen with VMP. I don’t know
this for sure, but I think if you
use soundcard with a decent clock
such as a UMC202HD as the master
output device this becomes the
reference clock. I could be wrong
as this is not made clear.
However, I am sure that VMP is
much better than any other virtual
soundcard solution that I could
find 18 months ago. It also has
ASIO on the virtual inputs which
has much lower latency and does
not get mangled by Windows.
You can monitor any signal via
the main output device. Like a
real mixer it as solo buttons.
Regards
Conrad PA5Y
i use potatoe from the same
company ... works superb
also downloaded vac plus vac_a
and vac_b and hificable
so now have 4x vac besides the 3
that potatoe brings with .. means
7 virtual cables used here
together with the full blown mixer
(and additionalli installed
lighthost and a few vst plugins to
give my audio a better punch and
sound)
so .. i can highly recommend the
mixer and the virtual cables
greetz sigi dg9bfc
Am 28.08.2021 um 18:30 schrieb
Max Mucci, N5NHJ via groups.io:
Hello Gedas,
A very helpful software mixer I
use for almost everything:
VOICEMEETER
by VB-AUDIO – The world´s most
used Virtual Audio Mixer &
Sound Tool
Friday, August 27, 2021,
5:23:20 PM, you wrote:
Using a RSPdx with SDRC V3.1
and Laptop with W/10.
All works aok but then I had
the bright idea to install VB
Audio to get some VAC going so
I could run WSJT etc.
That went smooth and was able
to make many FB decodes
overnight.
1. I wish there was a way to
be able to hear what the RSPdx
is tuned WHILE it's audio is
being ported over to WSJT via
the VAC. Is there an easy way
of monitoring what the VAC is
transferring?
2. The next part has me
scratching my head......I am
done with WSJT and just want
to do some listening on this
W10 laptop with the RSPdx.
When I go to
SDRC/OPTIONS/AUDIO/PLAYBACK/DEVICES
I can see my Realtek PC
speakers on one line and the
VAC on the 2nd line.
I select the Realtek PC
speakers, hit OK then re-start
SDRC hoping to be able to hear
the receiver via the speakers
but get zip. Is there an easy
way to switch from one to the
other? I thought the OPTIONS
tab is where I make this
selection but apparently not.
Thanks
Gedas, W8BYA EN70JT
Gallery at http://w8bya.com (under
repair)
Light travels faster than
sound....
This is why some people appear
bright until you hear them
speak.
----------------------
73 de Max, N5NHJ (I8NHJ)
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