Use MIDI from DAW to change Slider

[demoralized]

Hello,
I have been searching for several days for a solution and didn't find anything so I would like to post my issue.


My goal is to change a knob/slider in QLC+ continously via Midi, that comes from a DAW. My Setup is:

Reaper > MIDILoop > QLC+ > USB2DMX > Lightfixture

Everything works perfectly fine so far. I am able to use the Velocity of a Midinote to change the intensity of a light. I would like to be able to program a Fade In for example, but I stumble upon a problem.
When I program a succession of velocity changes, the Light fixture flickers. The Fader of QLC+ always snaps back to 0:


The Flicker comes from the Midi "note off" signal. Since velocity is the speed of attack it apparently can only be send once per note.



Is there a way to iron this out? I mean a Hardware Controller can be assigned as faders trough the I/O Profile tab. Maybe something similar can be done with MIDI from a DAW?


Some additional Info:
I have to add that I am not sure if picking up something continuous like a Pitchbend wheel or Prgram Change is the solution I am looking for. The Reason is as follows:

The goal is to control several segments of a LED bar independently. It has a 24 channels mode and I would like to use each channel as a knob/slider so I can make wave effects.
My current workaround is to create a scene that has a attack and release timer attached to it, but that creates a whole lot of extra knobs and clutters my midiroll and virutal controller, since I have 24 regular ON/OFF buttons and additional 24 Fade IN/OUT buttons .

I hope I have described to problem properly and I am thankful for any idea that I can try.

[janosvitok]

Stupid question: Can you make Reaper NOT send the Note Off messages? Using legato for the notes or whatever?

Jano

[MichelSliepenbeek]

Stupid question: why not use a Control Change?

[demoralized]

@jano
I tried to find a way to filter these out but I couldn't. It always sends a Note Off message. There seems to be a difference between a "Note ON, 0 Velocity" Command and a "Note Off command", but my midi monitor always showed a "Note Off, 0 Velocity". The Problem is I need some kind of Note off Message, or at least have some kind of ability to deactivate the light. Possibly with a Velocity 1 command that gets interpreted as 0/255 light intensity, that could be interpreted by a QLC modifier. But that is a secondary problem.

I read trough all the reaper forums but there wasn't anything concluding. Tried several VST filters but to no effect, since they all let the Note Off command trough. Even tried to scrips something with GTP but wasn't successful either (because I lack programming skills).

@Michel
Control Change does work but I am limited to a couple of sliders. The LED bar has 24 Channels, and I can't map that many control change / program change / mod wheel parameters, and I would also loose the overview since the Reaper Midroll is not made for that kind of dataoverview.



My current solution is to have 3 different scenes per Channel, with different Attack and Release times to have strobe, fade in/out and decay preprogrammed effects. That takes up 72 Midinoets for one light. If the velocity changes could be interpreted the way I like, I would be able to reduce it to 24 notes.
I also tried to play around with the release time option in QLC+. Apparently there is a 60ms delay, based on my midimonitor between a note off and note on command, where the light is forced to be off. I tried to bridge that gap, but I am loosing the stroboscope effect, if I need one.

[demoralized]

I found a solution. I wrote a script that picks up the "note on velocity" and replaces the "note off velocity" with the same value. That works quite well currently.

[edogawa]

You also could make your MIDI notes much longer and overlap, so much that the first note off comes after the last note on in a ramp.
I tried that just now in linux, with ardour sending similar velocity-ramped notes to a QLC+ level fader, and the flicker (which was noticable with legato notes) disappeared in QLC+ preview..

[demoralized]

That is interesting. This solution didn't work in reaper. Overlapping had no effect.

[Zeif1n]

I found a solution. I wrote a script that picks up the "note on velocity" and replaces the "note off velocity" with the same value. That works quite well currently.

I have the same problem, would it be possible for you to share the script you wrote?

I haven't found any working solution, I have Cakewalk Daw in use, but the problem is exactly the same as you had.