[LAU] Ardour's Mixer fader for MIDI tracks

[Len Ovens]

On Thu, 16 Mar 2017, Ralf Mardorf wrote:

> what exactly does the fader of Ardour's mixer for MIDI tracks control?

It depends...

It depends on where the fader is placed (or where the synth is placed).
If the fader has only a midi stream to deal with, it controls velocity. 
The values shown are (looking at latest git) 0 to 2. This is gain. with 
the fader centred at 1 velocity in = velocity out. if the fader is at 1.5 
then velocity out will be velocity in * 1.5. (eg 64 in * 1.5 is 96 out).
However, if the Fader is placed after the synth (as is default). It deals 
with the audio that the synth puts out. It does not control a synths CCs 
(which would only give 128 positions) but rather fades the audio after 
that. This gives .1 db steps with the mouse wheel, but less is possible 
with OSC or script and a mackie control surface (or X-touch etc) with give 
1024 positions (though Ardour will deal with all 14 bits if the controller 
does, Mackie sets the 4 lowest bits to 0).

I do not know if the fader affects the MIDI velocity after a synth or not. 
I would not expect it to (as a user) because I might feed it to another 
track or buss or external synth... maybe someone else can comment.

>
> I noticed that CC 7, CC 10 etc. could be selected by the editor, in
> addition to the mixer's fader. CC 7 does control the volume, while the
> mixer's fader seems to have impact to the note velocity.

Automation in the editor is a different animal and controls other things 
besides just the fader. The fader as seen in the mixer is a straight gain 
block whether applied to midi or audio.


--
Len Ovens
www.ovenwerks.net