2010/2/16 Mark Brown broonie@opensource.wolfsonmicro.com
On Tue, Feb 16, 2010 at 03:32:01PM +0100, Lennart Poettering wrote:
On Tue, 16.02.10 09:24, Jaroslav Kysela (perex@perex.cz) wrote:
Line: 0dB..47.81dB # seems correct -47.81dB..0dB Line Capture: -0.18dB..23.81dB # seems correct -17.81dB..6.18dB
Hmm, how did you choose where to put 0dB?
The Line one looks like someone got attenuation and gain confused, which is a fairly common mistake for people to make when copying information from one place to another. Possibly a similar thing going on with the Line Capture control, plus a fixed 6dB gain (which may well be a separate amp...).
Correct me if I am wrong
0dB point is needed when you recording from line-in by connected loopback cable to line out.
The captured signal is supposed to be the same as the playback signal when you set both playback volume and capture volume to 0dB ,
if you set playback volume over 0dB , clipping occur in the captured signal ,
if the playback volume is less than 0dB , captured signal will be less than the playback signal.