[LAD] Calibrating sound cards

[Lee Revell]

On Mon, Apr 14, 2008 at 5:15 PM, James Courtier-Dutton
<James at superbug.co.uk> wrote:
> Hi,
>
>  Is there a recognized method for calibrating a sound card?
>  e.g.
>
>  For Playback, one sends a sample .wav PCM file to the sound card, then
>  measure the analog output from the line-out.
>
>  If the sound card itself provides 0dB of Gain, what should be the
>  measured figure?
>
>  Can this be done with a simple AC volt meter?
>
>  There seems to be some debate, with regards to ALSA, as to whether the
>  line-out is at the correct level if one sets all the ALSA mixer controls
>  to 0dB.

Wouldn't this require developer access to every single device we
support?  With HDA intel this would mean every make and model of
laptop and motherboard on the market.

Lee