Logic behind negative 'Fade Out Linear Value'?

Question

Hi,
our team is designing an ipad app. We did some testing on audio fades in Audition and found a 'Fade Out Linear Value' of -15 (over 2000 ms) is the perfect setting.
However, we now have to pass on this information to a development company in a design document. I tried to find out what the logic is behind this setting so it can be mathematically explained and reproduced in iOS, but I cannot find it in the documentation.
So does anybody know the logic behind this setting, or does anybody have an idea on how to pass on this information to an external development company in a design document?
Greetings,
Pieter-Jan

Answer 1

I don't think that any of us will have the faintest idea, quite frankly, although I'll check and see if there's any obvious logic to it. IIRC, last time I checked this I couldn't see any direct correlation to anything else at all.
The only way that I can think of detailing this to somebody else would be to record a constant amplitude sine wave in audition, apply what you think is your ideal fade,  and then measure the amplitude of the sine wave at fixed intervals along it. Make a note of the dB figures and the times, and send that to them.