LF FM doesn't seem to work as expected

I’m having issues with the LF FM input. In the manual, it says it’s good for pitch envelopes which I was looking to use it for when I discovered things don’t seem to be working as I’d expect. In the manual, it also says it accepts -5v/+5v and can change the pitch by -6/+6 semitones.

When I plug CV into it however nothing seems to happen. I’ve made a video which hopefully clarifies the problems I’m having.

I’m running the latest firmware and have done a callibration.




I have not received any firmware-related reports about LF FM issues, so my best guess is the audio jack is damaged or defective patch jack or perhaps has a “cold solder”, meaning that it the solder work didn’t properly connect the PCB to the jack. It might be possible to identify a solder issue from a photo of the back of the panel. In any event, this problem means webneed to process a return. Have you experienced any other issues?

I’ve not had any other issues (aside from having to power off & on the module to clear distortion.)

It’s strange that the input does do something especially when sent a fast CV.

I will email you a photos and move the conversation to email.


That sounds like the right call–I think you’re collection of issues probably pertain to your specific unit.


Kid Yoshi and I have been discussing this over email as it appeared to me to be a problem with his specific unit initially. Just a little update in case anyone else is running into this issue. My latest comments to Kid Yoshi on email:

I have replicated your issue on both the unit you returned to me and another unit in my studio. So, it’s definitely not related to the specific units you’ve had in your possession. I’ve also come to understand why my testing was previously inadequate–I believe I tested this parameter with fairly fast LFOs looking for a vibrato-type effect which is quite achievable. This does not properly test whether the parameter covers the +/- 6 semitone range claimed in the manual. All that being said, observations so far do not resolve the question of whether it a hardware or software issue at its root. However, I do suspect (and hope!) it’s the software. I’m reviewing how I apply this parameter in the synthesis and realized that I cannot explain how it would achieve +/- 6 semitones effect. So, I’ll study it further and hopefully identify a firmware solution.

My LF FM input acts weirdly too, never managed to apply vibrato kind of modulation.

Hi, we’ve got a fix for this on the way. The firmware is prepared, but as a Mac user I’ve been having trouble properly debugging the Windows update script which is reported to have a problem. I’m hoping to resolve that in the next couple of days and then I’ll post 1.0.3 which should resolve the LF FM misbehavior.

Hi folks,

Thanks so much for your patience. We’ve got a new firmware version available that addresses the issue with the “LF FM” input. Information is available here: