ES9 VCV detuning issue

Hey all, Anyone else experiencing this? With nothing plugged into the es9, if i just virtually plug the first 4 “from device” outputs from an audio 8 module (with es9 as the device) into any initialized 4 oscillators in vcv rack, they are detuned and dont track v/oct properly. I get the same detuning using “merge” and a “polyphonic” cable into any of the poly enabled modules too. Sure i can tune each oscillator in vcv but the tracking is barely useable within one octave.

Is there a calibration procedure for the es9? I have the dc blocking off of course. I dont know what im missing here? Ive tried to feed the es9 signal from both a tetrapad with tete in chord mode and the 2 outputs of intellijel scales, same result. Any help would be rad thanks!

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Hi and welcome to the forum!

Have you tried this module:

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I have the same wonder as you. Using a volt-meter in Rack I expected a signal from ES-9 to be 0 volt if un-connected, but it’s not, it has a small offset. Strange. There’s no mention of calibration in the user-manual.

Yeah, maybe this can be used to remove the offset from the ES-9. Should probably try and connect the Calibration Input to a VCO (sine wave) in Rack, the Pitch CV Input to the CV from ES-9 and Pitch CV Output to the volt-meter, and see if it removes the offset. Maybe you’ll beat me to it @tthogs :slight_smile:

NYSTHI has a free version… works just as well!


Omri, has a video on this subject,

What’s it called?


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Expert Sleepers modules are not hardware calibrated. Meaning if you send exactly 2V (for example) to the ES module, you won’t get exactly 2V coming out of it. iirc, the further you get away from around 0V in either direction, the greater the inaccuracies become.

This is why ES has the Silent Way Voice Controller module for VCV - it compensates for these inaccuracies in the hardware and gives you perfect tuning. As a further plus, it also compensates for tuning inaccuracies across the range of hardware analog VCOs (ie. it compensates for inaccuracies in both the ES and the VCO hardware). Nysthi Tunathor does the same thing.

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I attached a picture here where I calibrated 4 inputs of the ES9 with the voice controller. Im still getting detuning afterwards. I’m starting to wonder if the “merge” module is causing this.

Have you run the calibration using the calibration input? You need to calibrate first.

The way it works is like this. It sends various test voyages to the VCO and then listens back to the frequency the VCO outputs. It knows what the frequency should be and calculates the difference between what it expects to hear and what it actually hears. Once calibration is done it then applies a +/- offset to the voltages sent to the VCO to compensate for the difference.

its best to use a sine/triangle wave output for calibration, square/saw have too many harmonics that can confuse the frequency analyser. Once calibrated you can use whatever outputs you like of course.

I would try it just monophonically first, and use Nysthi Hot Tuna before/after calibration to compare the frequency/pitch of notes coming out of the VCO.

You can tell if Merge is causing an issue by just taking it out of the equation and using 4 x VCO-1 instead.

In your image above you would need to run calibration with each of the Voice controllers.

UPDATE: actually there is something else going on here maybe. The voice controller is really designed for controlling hardware VCOs - ie where VCV is doing the sequencing, that is sent out of the ES-9 to a hardware VCO, and the sound then comes back into VCV.

You are trying to do it the other way round - sequencing VCV from hardware. I don’t think Voice controller will work in this scenario because the voice controller is generating the frequencies, sending them to VCO-1 and listening to the result - which is going to be perfect because the signal path is all internal VCV - it is not going through the ES-9 at all.

Thanks for helping me, im finally getting something useful. i know how the calibration works and i have been calibrating each module independently.

Basically the issue is this, even after calibration, the base pitch for each output of the es9 still needs to be fine tuned. You can see in the sceenshot ive had to fine tune each module to get the same pitch. If i do this it tracks perfectly. But the issue is that basically makes “merge” useless unless i put some kind of offset module between the voice controller and the v/oct input of each input on merge. Is there an offset module that has 4 channels that i can save a preset on? Thanks!

Read the update at the bottom of my post above. Calibration is not doing anything in this scenario. You are essentially using fine tune to manually calibrate each VCO to compensate for the ES-9 offsets - and while that will work for one particular note, the offsets are not constant across the range - so a fine tune offset that works for C4 for example probably won’t work for C2 or C6.

I’m not sure if there is a solution for you or not. You could try sending your pitch CV output out of the ES-9 and straight back in again when running the calibration. But then the offset applied by the calibration will account for differences in both the ES-9 outputs and the inputs - and when you connect your Tete you will just be using the inputs and not the outputs so the calibration will be a bit off I would imagine.

The ES/Silent Way ecosystem was originally created to allow sequencing of Eurorack from a DAW - not so much the other way round. But I will think look into it some more.

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Lame. I really wanted to use the Tete tetrapad combo to make sequenced chords in vcv. I guess thats a weird use case. Thanks anyway

What about just trying a quantiser? The offsets are not that bad so just having a quantiser that pulls each voltage to the nearest semitone might do the job?

So pitch CV from Tete, into ES-9, and then into a Merge, then into a poly quantiser before the VCO-1. Worth a try.

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Hi! I think a quantizer could help you, just activate all of the notes and it will quantize the incoming cv to the exact values that are ‘in tune’.

Beat me to it :slight_smile:

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Thanks guys I will try that tonight when I get home. Hopefully it will have me saying “very nice” :wink:

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Cool, I’m curious to know how it will work. Don’t forget that you can use a polyphonic quantizer as well so you can save some space and CPU. I think the best will be the one from JW, just to see how it works.

Stoermelder has Affix and micro Affix that can be used to add offsets to polyphonic signals, if you still wish to try this, but the use of a quantizer may be a better option.