Re: gain-mapping - was Re: OSC next

Robin Gareus <[email protected]> Sat, 14 May 2016 17:13:07 +0200
Newsgroups gmane.comp.audio.ardour.devel
Message-ID <[email protected]>
On 05/14/2016 04:41 PM, Len Ovens wrote:
> 
> The other method of doing the same thing, is to continue to use the
> internal fader math and add an offset of -0.006990539841353893 to the
> 1024 value. This would make 800 = 0dB and full scale just slightly less
> than +6.

good point. How did you compute that number?

over here

  1.0 - (2 ^ ((198 * (800/1023) ^ (1/8) - 192) / 6))
= -0.000805030


A better solution would be to use 800 / 1024 and offset by +0.001902344
for the follow up:

> Shifting right to 7 bits for CC gives that magical 100

That also means you need to shift the divisor: 1024 -> 128
(and not 1023 to 127).

> I shall have to try both to how they "feel".

+1 :)

ciao,
robin