When I first plug-in the Minitaur, the MOD section is functional.. I can change the LFO Rate, the VCO LFO AMT and the VCF LFO AMT.
As soon as I change the patch though these functions cease to work. I get no modulation whatsoever. The LED lights up even.
I’ve had problems with the Minitaur since the get go (just got it back from the shop after a month - bought it a few days before I sent it on), I’m hoping it’s maybe just something I’m missing but it doesn’t seem like it.
You can change it actually, if you have the latest firmware and the editor you will find an option in the latter one’s settings page:
-Load preset Mod Wh On/off
Try changing it to see if it fits your needs. Remember that you can save each preset with a specific mod wheel amount, which might be useful too.
It was a feature originally, meant for those that did not have traditional keyboard controllers (e.g. you could pulse the GATE IN with a sequencer or drum pulse and then tweak modulation rate and amount for VCO and/or VCF). But ONLY if you had a mod wheel to set the absolute modulation to an amount; recall that the two pots in the MOD section on Minitaur’s panel are relative.
You would need to move the mod stick/wheel up and back on your keyboard to assume ‘normal’ behavior where normal = how a keyboard and synth module usually work.
But have been issues with LFO stopping or behaving strange in older versions of firmware; not sure how old your Minitaur is but I’ve read that the latest is pretty good.
And as ‘bichuelo’ said, there is a feature to have a specific Mod amount saved with a patch; (the Taurus III did this, which is handy because some patches use a specifically dialed in amount of modulation as part of the sound).