[Elecraft] Performance of internal USB sound system compared toexternal one?

[Ed Muns]

All my other Windows sound devices with two channels have independent level
controls, one for each channel, plus the ability to link them together and
adjust equally.

For whatever reason, I've often found that I need a different level setting
to set the no-signal baseline in the decoders for each receiver.  In theory,
perhaps that shouldn't be necessary but in practice it is.

Ed W0YK

-----Original Message-----
From: guyk2av at gmail.com [mailto:guyk2av at gmail.com] On Behalf Of Guy Olinger
K2AV
Sent: 14 June, 2016 14:24
To: Ed Muns
Cc: Jeff Stai; Elecraft Mailer
Subject: Re: [Elecraft] Performance of internal USB sound system compared
toexternal one?

To be strict, a stereo gain control (volume is a misnomer) will adjust
both channels equally, then if supplied, there is a balance control
which creates a ratio of left to right channel gain which is
maintained regardless of the gain control.

What you seem to be asking for is the ability to treat left and right
as if they were independent channels, which I would guess is very rare
in drivers.

"Volume" depends on channel gain and a lot of other things. At the
input of various end user devices, the volume range is specified. The
volume coming from upstream devices can depend on a lot of things, RF
gain, AGC settings, conditions, and possibly others in addition to
codec channel gain.

Why would you need a stereo balance control for use in data modes?
Dual RX and "diversity" decode? If a K3 dual RX diversity kind of
operation, why wouldn't equal gain on left and right be required?

Regardless, 73 and good luck,

Guy K2AV

On Tue, Jun 14, 2016 at 4:54 PM, Ed Muns <ed at w0yk.com> wrote:
> Yes, there are two receive audio channels for the Main and Sub receivers
in
> the CODEC.  The Windows driver level control adjusts both channels
> identically.  If there is any unbalance or for some reason you want to
> independently adjust the two channels, it can't be done.  The driver
> communication with Windows should trigger the stereo level control, but
> doesn't.
>
> The CODEC is the TI PCM-2902.
>
> Ed W0YK
>   _____
>
> From: Jeff Stai [mailto:wk6i.jeff at gmail.com]
> Sent: 14 June, 2016 13:15
> To: ed at w0yk.com
> Cc: Robert Wood; Ken Arck; Elecraft Mailer
> Subject: Re: [Elecraft] Performance of internal USB sound system compared
> toexternal one?
>
> On Tue, Jun 14, 2016 at 12:44 PM, Ed Muns <ed at w0yk.com> wrote:
>
> One issue I have with the K3S CODEC is that Windows installs a monaural
> level control rather than separate left and right channel level controls
for
> the two receive audio streams.  There also seems to be some kind of AGC
> action going on where the levels actually change over time.  This appears
to
> be eliminated by the chip manufacturer's CODEC driver that I found online,
> though it is still monaural.
>
> You still have a left and right channel, you just can't set the levels
> independently, correct?
>
> I haven't seen the AGC issue, but maybe I haven't noticed the levels
> changing very much. Who is the chip mfr?
>
> Thanks! - jeff wk6i