Need way to shift patch from A440 to A415

I (and my partners in crime) blend VCV with acoustic instruments. We have a performance coming up where we need to shift to instruments tuned to A415 Hz. We use several modules that are “set” to A440…some Aaron Static stuff and some other things. Adapting our current patches, is there perhaps an “easy” way to do this, like some VCV default to set the Hz of A? Or, do we have to go make adjustments to all modules that would be affected?

Thanks in advance for your help!

As far as I know there is no menu-like setting.

But you can tune your Oscillators pretty easily using HotTuna of Nysthi Just find the correct offset to adjust the tuning of the pitch voltages. Some oscillators have a fine control built in to do the offset, but any will do. I would have to see the patch to answer more precisely though.

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Depending on how your patch is configured you can just add the appropriate constant to your v oct source and it will shift the entire patch. If you have multiple pitch sources you’ll need to get all of them of course.


@ellencooper1 - Will this be for live performances, or pre-recorded?

Will there be a midi controller input (with a possible built-in tuning) for a live performance, or is it all VCV sources like sequencers and such?

Sounds like a Baroque pitch tuning. Will it also involve just intonation tuning vs. equal temperament tuning?

FWIW, I don’t see anything in “settings.json” that looks like it has to do with a global tuning setting. That would be a nice feature to have though. Failing that, I’d just surrender and do it the way @baconpaul suggested.

Thanks! That helps for tunable things like VCOs, but some modules have “built in” chords, etc. Those are the trickier ones…

For fun I found this , maybe it works , maybe it won’t

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Hmm… good questions. Yes, they are Baroque instruments, but we’re working (for now) in equal temperament (phew). We’ll have multiple midi controllers, for various things, but I will check to see if any of them can assist in some what with built in tuning–great suggestion. Thanks!!

whoa–that’s wild!

Ok, you have to do it the way @baconpaul says then. (You could merge all v/oct signals into one polyphonic offset module, split them after the offset and patch all cables to their inputs. So you can adjust the tuning with one knob for ease of control.)

With HotTuna you will find the right amount of constant voltage you will need. For instance from A=440.00Hz to 415.00Hz would be: -0.0844V

415Hz is a rather good G# in 440 tuning as you can see… so if you only need this, you could almost transpose everything one semitone down. But the more exact and flexible way is using an offset of course.


Excellent–thank you! That was kind of an approach I was considering…but wasn’t quite sure how to go about it. I’ll give that a try.

If you are playing with folks using ji or meantone or so on, your best bet is to pick up oddsound MTS esp which will tune many of your virtual instruments and has a midi in source which retunes. Works great.

You are correct thst a lot of cv manipulators in rack are not tuning aware though. So things like chord stack cv modules will assume 12tet and many quantizers will require custom configuration

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Since v/oct is linear and frequency is f0 2^v you can figure out the linear offset for a frequency shift using log2(desired_a / 440). For instance log2(415/440) = -0.08439218729 (the result you saw). If you want to do direct linear tuning adjustments this may be an easier approach than dialing it in with a tuner (although its lovely to know the later also works :slight_smile: )


True. I always forget the math… haha.

Being a performing musician I tend to use “instruments” first. This is one of the things I really enjoy of this forum -it deepens my understanding and it invites me to start improving my maths reading all the expertise of developers here. (I should ask my son to teach me as he is a mathematician. Maybe I will be able to start coding then -as the math still scares me of a bit :slight_smile: )

In most coding you don’t need any math - it’s sort of a myth, and also really early programming was often to solve simple math problems (like rocket trajectories).

I always joke that I’m always the “math expert” wherever I work (programming), by virtue of the fact that I can actually do all the math I learned in high-school. That would be trigonometry, algebra, and introduction to calculus. A huge majority of programmers can not make a similar (weak sounding) claim. (which is fine, of course!)