Bug? MIDI effect "Root Note" not +/- 1/12v

In the MIDI effect, with a default “Root Note” value of 60, Middle C (C4) outputs 0.00V, and other C values are in tune at -1.00V, -2.00V, +1.00V, +2.00V, +3.00V like I expect. (I’m measuring the voltage with an oscilloscope)

If I attempt to transpose the track up or down by some number of octaves by changing the Root Note from 60 to other multiples of 12, I expect Hermod to output voltages that are exact multiples of 1 (no decimal places) for various C notes, eg. 1.00. However, I’m seeing voltages that are substantially different, eg. 0.95, 1.06, which results in some very out-of-tune synths:

In practice, what this means is that in order to transpose up 2 octaves, I need to set Root Note to 85 (not 84) and Fine Tune to 60 (!) and I need to use a scope or a tuner to do it, because I have no idea what the drift is going to be. I feel like I should just be able to set Root Note to 84 and not adjust Fine Tune at all.

I’m seeing this behavior on multiple tracks. Here’s a different track:


  • With a Root Note of 60, some tracks output non-exact voltages, which is easy enough to adjust with the “Fine Tune” setting
  • In the online manual it’s called “Root Note” but in my Hermod (fw 1.30) it’s called “Root Note 0V”

Is anyone else seeing this?

I’m also going to file this as a bug report.

I concur… though for me its pretty constant

basically, to be in tune its +13 semis per octave -20 to 25 fine tune
so if we assume fine tune = cents , then it looks like its around 80-85 cents out/per octave.

(I think it is cents, as if I I can go to root note 85 + 60 cents and voltage is pretty close to right)

note: I’ve just recalibrated hermod, so my voltages are pretty much spot on for all note ranges where root =60, and with 0 fine tune.

It behaves like this for me as well. Shifting the root note 12 causes everything to be out of tune. I’ve used the Scale > Interval effect to shift octaves and that works. What’s puzzling is why it Root Note and Scale > Interval are different.

I’ve reported to squarp, and they say they are going to take a look.

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What email address did you use to report it? I’ve reported 2 bugs in the last week and haven’t gotten any kind of response. /cc @squarpadmin

main point of contact is their contact form on their website.

I usually use this for ‘new’ bugs, but I do sometimes reply to previous responses (contact@squarp.net) where the issue is potentially related… e.g. I felt this was kind of related to some cv calibration issue we were already discussing.

they are pretty busy, so can take a few days… if Ive not heard anything after a couple of weeks i sometimes ‘ping them’

note: I try to be very clear/precise with bug reports - whilst keeping the ‘extra’ info to a minimum - I also make sure I test it throughly, including trying different scenarios etc. Im a software developer, so I’ve a pretty good idea what is needed in a bug report.
it’s common sense really, the quicker/easier it is to understand your report the more likely they can do something with it quick.

(btw: this is not aimed at you - i’m not suggesting my report was better than yours, rather just reminding readers generally the way I find I get the best response from any ‘software’ company)

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Yep, ok. I’ll just wait for a response. Keep us updated if you hear back!

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Hope it is alright I post this question here, it seemed very related.
I just experienced a similar problem and came here looking for answers. I am actually trying to use the root note parameter to transpose a sequence using external MIDI notes from Ableton. However, these do not even track properly over 1 octave, even at 60. It might be the CV output isn’t sending out the right voltage like you describe, or the CV input isn’t properly tracking v/oct signals.

Also, I feel like it’s really strange that the Hermond does not let you transpose an entire sequence with just external MIDI information. I am sending notes from Ableton via USB to Hermod, but right now I have to assign both a cv output from one of the sequencer tracks and a cv input to this purpose. Is it really not possible to route the MIDI notes from Ableton internally in a way that allows you to transpose the sequence? Pretty much all analog sequencers work like this, and it feels weird that squarp would move away from something like that… Am I missing something?

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Having the same issue here.
playing midi note c5 registers as 0v which is quite high

this issue no longer exists, it was fixed in 1.4
also the behaviour of the root note has changed subtly since this post was created.

c5 is 'reasonable, given we have -5v to +5v, so C0 to C10
however, you can change this, by changing the midi fx root note… thats what its for :slight_smile:

Im going to close this post, as the OP issue is no longer valid for the current version of the OS.
@radar , please create a new post if you need more info, or if you have an issue you can contact squarp via the contact form on thier website.

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