'Twas brillig, and Raymond Yau at 19/06/10 01:39 did gyre and gimble:
To simpify the implementation of the slider , a new "PA dB scale" is used by shift those +12dB(base volume) to 0dB and insist that every sound card 's minimum_dB is -inf dB ,
No. -inf dB is -inf dB. If the card does not go down to -inf dB, PA will extend the range in software. If a card only goes down to -12dB minimum the range -12dB -> -infdB will be done in software. Lennart explained this very clearly to you already.
This mean that all sound cards will now have same "PA dB range" , the volume slider does not need resize or rescaling any more. This is why they prefer to use percentage to make you believe their calculation of dB is correct
WTF? "prefer to use percentage"? What the hell are you talking about?
Col