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

Rene Herman rene.herman at keyaccess.nl
Sat Apr 12 21:32:50 CEST 2008

On 12-04-08 15:35, Lennart Poettering wrote:

> On Sat, 12.04.08 12:15, James Courtier-Dutton (James at superbug.co.uk) wrote:
> My I thus assume that we can say that for all but the last element in
> the series 0db means avg input power equals avg output power, and for
> the last one 0db means max? That would fit on what you are saying but
> also match my usb speakers, not depending on the existance of a
> "Master".

If we add in ISA cards, it's not a very generic assumption at least. For 
example on my cs4236, "master" is -94,5 to +12 dB with 0dB at "87" in the 
integer scale.

It's a "Master Digital Gain" -- not sure what that "digital" implies as it 
very much seems to be positioend in the post output mixer analog path...


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