[LAU] digital volume sounds better at 0 dB?

[fons at kokkinizita.net]

On Fri, Jun 18, 2010 at 05:57:46PM -0600, Bearcat M. Şandor wrote:

> > That means that you should turn down the power amp gain
> > quite a bit.
>
> This is a low powered 10 watt max amp (class t chip)

That doesn't mean its sensitivity is low as well.
 
> The alsamixer volume controls make no difference at all to jkmeter, but adjusting the
> volume on mplayer does. Is this the expected behavior? 

Yes.

> I was not sure how to activate K20 or K14 given 
> jkmeter's interface.

See Robin's post.

> You mean individual application volume controls as opposed to the sound
> card mixer is preferred?

If the application's gain control works on floating point
samples, yes. 

The sound card's gain control works on the 24-bit signal.
For a gain below 0 dB it reduces the maximum available
output as well. For example if you set it to -18 dB (which
is 1/8 linear gain), the DAC will never use the upper three
bits - you now have a 21-bit system.

If the volume is set using a floating point gain control, and
the soundcard gain remains at 0 dB you have the full range of
the DAC regardless of volume.

Ciao,

-- 
FA

O tu, che porte, correndo si ?
E guerra e morte !