I am experiencing a unwanted vibrato effect on my MIDI tracks, and I would like to figure out why this happens. I am using ACE Fluid Synth with a piano.sf2 soundfont, on Ardour 6.9.0 running in Ubuntu 22.04.4 LTS.
It seems to only happen if I load the track with multiple chords. And it seems to go away if I hit the “Panic (Send MIDI all-notes-off)” button in the Transport menu. But comes back as soon as I play a certain part of the track with multiple chords.
I am new (or a bit rusty) when it comes to music making and sound production, and therefore I would like to ask here if anyone has a solution or can help me with the problem.
Here you can find a version of the track (with unwanted vibrato), so you can hear what I mean:
Is your mod wheel on your MIDI controller causing this ? Aftertouch settings on a controller may also be causing this. Try using the ACE MIDI Monitor plugin and see if it shows MIDI messages being sent that could cause this.
There is likely a way to remove those MIDI mesaages from the track, but I am not at the computer at the moment. The Ardour manual should have that info.
Thank you for the quick reply. That was definitively the problem. Not so much the mod-wheel itself, but it seems to be coming from the keys if I press them a bit too hard or too long. The keys are touch-sensitive, and my guess is Ardour is picking up the signals in a wrong way giving every key the same signal/effect as the mod-wheel.
Is there a way to modify, or mute, those signals coming from the MIDI Keyboard? I would much rather fix it on the keyboard, instead of having to go over the track every time it happens.
That is a feature called aftertouch. It allows for expressive control when using something like a string sound, but as you found is not typically useful with a traditional piano-type sound.
You did not state what keyboard you are using, but there may be a way to turn off those messages from the keyboard.
It may be easier to change the settings on the synth plugin to ignore aftertouch messages.
ACE Fluid Synth is a simple plugin, I would start by checking the chorus settings, disable chorus if it is currently enabled. I do not see any other modulation options in ACE Fluid Synth, so that may be all you need to do, uncheck the Chorus Enable control.
These are some great free MIDI plugins that will help with filtering out the aftertouch on the input, or the recorded MIDI track as well. Place the correct plug in before the instrument plug in.
Your keyboard manual should be able to tell you how to disable ‘After-Touch’, if possible.
I am using a Arturia Keystep 37 MIDI keyboard. A mighty fine keyboard I find.
I tried to enable/disabling chorus in Fluid Synth, but that did not solve it.
The manual I found showed selecting between four different (force to value) curves, but no selection of Off.
The MIDI filter plugin is probably the best choice in the current configuration, but you could also try a different synth plugin which gives more control over modulation routing and which messages the synth engine will respond to.