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windguy2
2005-03-28, 14:02
How is the analogue volume controlled?
Is it lossless using shunt resistors in a chip or is it done digitally
therefore dropping bits?

The reason I ask is that I use a passive preamp driving a power amp -
if it uses shunt resistors in the analogue domain then I would be able
to use the remote to control the volume of my system without losing
resolution at low volume.

Robin Bowes
2005-03-28, 14:55
Jason wrote:
> Volume has always been controlled server side, which would mean digitally.
>

I'm sure someone more qualified will confirm this, but this is just
plain wrong.

The volume is controlled internally within the main chip in the SB.

R.
--
http://robinbowes.com

seanadams
2005-03-28, 15:06
Right now we are doing the volume in the CPU, for both s/pdif and DAC
outputs. The DAC also has volume control capability but we're not using
it at the moment.

Since the DAC is 24 bits, no resolution is lost (assuming 16-bit PCM
source) except at the ultra-low volume levels.

If you have a preamp then it's really ideal - set the preamp to the max
listening level you'd want to use, and then you can use the volume
control in Squeezebox.

On Mar 28, 2005, at 1:02 PM, windguy2 wrote:

> How is the analogue volume controlled?
> Is it lossless using shunt resistors in a chip or is it done digitally
> therefore dropping bits?
>
> The reason I ask is that I use a passive preamp driving a power amp -
> if it uses shunt resistors in the analogue domain then I would be able
> to use the remote to control the volume of my system without losing
> resolution at low volume.
>
>

seanadams
2005-03-28, 15:16
On Mar 28, 2005, at 1:55 PM, Robin Bowes wrote:

> Jason wrote:
>> Volume has always been controlled server side, which would mean
>> digitally.
>
> I'm sure someone more qualified will confirm this, but this is just
> plain wrong.
>
> The volume is controlled internally within the main chip in the SB.

Correct - it is, and always has been done in the client.