[alsa-devel] What does 0dB refer to? (Logitech USB Speakers)

[Rene Herman]

On 15-04-08 16:33, Rene Herman wrote:

> mute/minimal. Bit of a maintenance chore, and the usefulness depends on 
> how much level variation there actually is generally. Are we in essence 
> only talking about Lennart's buggy USB crap or is this more involved?

On that note, I just acquired an Audigy 2 (SB0240) that I'm testing with and 
now that I'm paying attention to it due to this thread -- its 0 dB setting 
is very significantly louder (with everything behind the line-out constant 
ofcourse) than the 0 dB setting on my TerraTec DMX.

James, I believe you are the emu10k1 person? Data:

TerraTec DMX = ESS Canyon3D (ES1970MS-3D) + Sigmatel STAC9704T

Creative Audigy 2 (SB0240) = Creative CA0102-ICT + Sigmatel STAC9721T (+ 
Crystal CS4382-KQ which seems to provide digital attenuation as well)

At 0 dB master the Audigy 2 is much louder than the DMX is and audibly 
distorts. Judging by hearing, keeping the master at -16 dB (60 in the 
integer scale) gets things about the same. Was that scale provided by 
datasheet or just guessed? Especially the distortion would seem to indicate 
that something is actually doing analogue amplification at the 0 dB ALSA 
setting...

Rene.