On Sun, 17 Aug 2014, Will Godfrey wrote:

On Sun, 17 Aug 2014 16:15:58 +0000
Fons Adriaensen <f...@linuxaudio.org> wrote:

On Sun, Aug 17, 2014 at 08:24:38AM -0700, Len Ovens wrote:

So Allen & Heath uses 127 levels on their top end digital control
surfaces, How do they do it? Well they have two different scales:
- fader: ((Gain+54)/64)*7f - also used for sends
- Gain: ((Gain-10)/55)*7f - this is preamp gain

Suppose you have *real* faders which have a range of 127 mm.
That's not far from a typical size on a pro mixer.
Would you ever adjust them by half a millimeter ?

127 steps, provided they are mapped well, and zipper noise
is avoided by interpolation or filtering, should be enough.

The real problem is that many SW mixers

* don't use a good mapping,
* and don't have any other gain controls.

The latter may force you to use the fader in a range
where it has bigger steps.

Well that got me thinking!

Presumably this should be set up as a proper log law, so even if the steps
represent (say) 0.5dB that still gives a control range of over 60dB

Actually, I got the idea that we should not only do that, but that we should use a gain or trim to put the signal in the area (level wise) where we have the smallest gain steps.

On a DAW, we sort of do this already by recording using the fader (and audio device gain) for trim and then mixing down using the fader for fine tuning. However, as I commented earlier, sometimes a harsh effect can introduce the need to:
- re-record the track
- add a gain section after the effect(s) before the fader. This may be as simple as using the output level the effect already has.

--
Len Ovens
www.ovenwerks.net

_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev@lists.linuxaudio.org
http://lists.linuxaudio.org/listinfo/linux-audio-dev

Reply via email to