Pitch to CV options (I know I know, but can it be DONE??)

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Roge Piltoney
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Pitch to CV options (I know I know, but can it be DONE??)

Post by Roge Piltoney » Wed May 20, 2020 3:57 pm

I know this question has been kicked around a lot, but it always seems pretty unresolved (probably because it is). Anyway, in my research, I've come across dozens of solutions. Does anyone have any experience with these? I intend to use my voice mainly, but also want to experiment with cello, guitar, and bass.

1. Convertor+ by sonicsmith: seems to have some unique "Audio Controlled Oscillator" technology. I've really only heard good things.
2. Disting: not too happy with how mine works, lots of glitching and the output always defaults to an extremely low and unpleasant note every time the audio input stops. Any way around this? I've already tried bandpassing/lowpassing the signal, and this gets rid of most glitching, but not the end-of-note glitching (haven't really been able to rig up a noise gate that sounds smooth and musical.
3. RS-35. Any good?
4. Sonuus G2M or B2M. Any good?
5. EAS mindreader (not to confident with SMT DIY)
6. A bunch of other random modules that aren't designed for this but seem to have been used with some success. I do not understand how these would work, even after looking at their manuals.
Wogglebug's influence input
Tides in PLL mode
Clock dividers (?)
Pulp Logic Entry Point
Falistri

Anything else I'm missing?

Thanks!

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Re: Pitch to CV options

Post by starthief » Wed May 20, 2020 4:51 pm

Most pitch trackers are going to get weird when the input signal goes silent. Normally you'd also pair them with an envelope follower and a VCA to silence the mess (on the Disting, the algorithm includes an envelope follower).

Some modules track pitch for themselves, but don't produce CV:

- Tides
- Kermit
- Starling Via Sync and Sync3

An advantage these have, besides being self-contained, is they tend to keep going at their current frequency when the input signal is lost. Like tap tempo on an LFO, only faster.


An actual analog PLL, like the Doepfer A-196, is more open and flexible about how you use it but also more touchy and flaky about how it tracks. The flaws give it character though. :) Unfortunately its internal VCO doesn't track 1V/OCT, so if you tap the CV to drive something else you'll get bad results -- but you can instead patch it through an external oscillator, and not only will that one track, the CV signal that feeds it can be used for still more oscillators.

You can patch a PLL without a PLL module. You need something to act as a phase comparator (I've found an XOR logic gate tends to work best, and you can patch them with Maths or Cold Mac although it's tricky), preferably a slew (if I remember right, Maths can't also slew if you've patched it to do XOR), and an oscillator. And patience and luck. :)

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by DonKartofflo » Wed May 20, 2020 5:11 pm

Excellent post above me!
I tried the rs-35 and what annoyed me the most was the constant and unavoidable slew and drift when it tracked signals. And yes i used compression, low pass/band pass filtering etc. Maybe cool for a novelty effect but not for any serious tracking especially on bass.
Now tides actually tracks quite well even in lower registers. I occasionally play my bass through it and kts always fun. Works best with compression and a comparator or a low pass filter.
If the disting algo is the same as the one in silent way, I hear you, less than great.

If you want synthy sounds, may i suggest a really aggressive fuzz (the devi ever bit works great) through a nice chorus and then a thick low pass filter?
This has been working wonders for me and it eliminates the issue of tracking altogether :tu:
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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by PhineasFreak » Wed May 20, 2020 7:01 pm

i has rs-35 and it works very well as long as you bear the following in mind: [found on some moog forum many whiles ago yet only took 10mins to find when beingg too lazy to go to studio and power uop the computer i saved itt on :P ]

Code: Select all

I have concept written by Bob Williams of Analogue Systems.
He posted this for me when I was asking about RS-35 Pitch to CV converter.
This is a patch which is basis for good tracking and you have some examples
on youtube.
Here it goes:

RS35 MASTER PATCH

MODULE REQUIREMENTS : 1 X RS35 EXTERNAL PROCESSOR
1 X RS95vco
2 X RS100/110 FILTERS (FILTER A/FILTER B)
1 X RS170 MULTIPLE
1 X RS180 VCA
1 X RS270 ADAPTOR MODULE


PATCH :BRING EXTERNAL SIGNAL (FROM AUXILIARY SEND ON DESK) INTO THE SYSTEM VIA RS270 ADAPTOR MODULE.FROM CONVERTED PATCHCORD TO 3.5MM PATCH TO SIGNAL IN OF ONE OF THE RS100/RS110 (WE WILL CALL THIS FILTER FROM NOW ON) AND PATCH ITS LOW PASS OUTPUT (ZERO RESONANCE) TO FREQ IN OF RS35.
MAKE SURE BOTH TOGGLE SWITCHES ON THE RS35 ARE IN THE DOWN POSITION)
PATCH OUT OF V-HELD OUT TO ONE SIDE OF THE RS170 MULTIPLE .
PATCH FROM MULTIPLE TO 1V/OCT OF FILTER A,FILTER B AND RS95
PATCH OUT OF RS95 INTO SIGNAL 1 OF FILTER B
PATCH OUT OF LOWPASS OUTPUT OF FILTER B TO SIGNAL 1 OF RS180
PATCH OUT OF RS180 TO DESK.
PATCH OUT OF LEVEL-V OUT OF RS35 TO OTHER SIDE OF RS170 MULTIPLE THEN PATCH ON TOWARDS LIN IN OF RS180 (TURN LIN POT TO MAX).MAKE SURE INITIAL GAIN POT IS AT OR NEAR ZERO
PATCH FROM THE MULTIPLE THAT FEEDS THE RS180 TO THE VC IN VARY OF FILTER B

BASICALLY A SUBTRACTIVE PATCH OF A VCO IS BEING FED INTO A FILTER WHOSE OUTPUT IS FED TO A VCA THEN ONTO SOUND REINFORCEMENT/DESK.

INSTEAD OF ENVELOPE GENERATORS OPENING AND CLOSING THE FILTER/VCA COMBINATION THE LEVEL-V OUT OF THE RS35 (IN OTHER WORDS ENVELOPE FOLLOWER) DOES THE SAME JOB
IMPORTANT!! THE LEVEL-V OUT IS DEPENDENT ON THE TRIGGER SENSE POT OF THE RS35 AND IT SHOULD BE SET SO WHEN AN INCOMING SIGNAL IS DETECTED IT LIGHTS UP (RED LED) TRY TO KEEP THE TRHRESHOLD TO MINIMUM.

INSTEAD OF A CONVENTIONAL KEYBOARD TRACKING THE PITCH OF THE RS95 VCO THE PITCH IS NOW GENERATED BY THE V-HELD OUTPUT OF THE RS35 WHICH IN TURN IS CONVERTING THE FILTERED INCOMING SIGNAL (BY FILTER A) OF THE EXTERNAL SOURCE.

NOTE:THE REASON THE INCOMING SIGNAL IS FILTERED (UNNECESSARY WITH VOCAL) IS TO REDUCE THE HARMONIC CONTENT OF THE GUITAR.THE RS35 WOULD TRY TO JUMP FROM ONE RESONATING STRING TO ANOTHER BEING CONFUSED BY THE HARMONICS.BY FILTERING DOWN THE INCOMING SIGNAL TO A SINE WAVE THIS CREATES A STABLE ENVIRONMENT FOR THE RS35 TO ACT UPON. A FURTHER ENHANCEMENT IS THE FACT THAT FILTER A IS NOW A TRACKING FILTER DUE TO THE TRICK OF SPLITTING THE V-HELD OUT AND SENDING IT TO FILTER A’S 1V/OCT INPUT AS WELL AS FILTER B AND RS95.

THE LEVEL V OUT POT SHOULD BE SET ABOUT ¾ WAY
CV IN VARY OF FILTER B MOSTLY IN ANTI CLOCKWISE POSITION (DEPENDING ON CUT OFF REQUENCY SETTING)

THE RS95 SHOULD BE IN WIDE MODE WHICH IS CONVENIENT FOR TUNING THE VCO TO THE SOURCE INSTRUMENT,FOR EXAMPLE THE OSCILLATOR SHOULD BE TUNED TO THE PITCH OF YOUR VOCAL RANGE IF THE VOICE IS BEING USED AS A SOURCE OF CONTROLLING THE SYNTHESIZER AND AGAIN,RE TUNED IF A BASS GUITAR IS BEING USED AS A CONTROLLER.

IT TAKES TIME TO FIND OPTIMUM SETTINGS AS EACH NEW SOURCE WILL REQUIRE A DIFFERENT APPROACH.THE FREQUENCY OF THE TRACKING FILTER A IS THE MOST IMPORTANT AS IT IS THE KEY TO PERFECT TRACKING

BOB WILLIAMS 3/07
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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by wuff_miggler » Wed May 20, 2020 7:09 pm

i would like to try the sonicsmith Squaver+ at some point
would love to hear it on good violin player or talented vocalist though, lack of comparison videos singing/playing a phrase then playing the same phrase through pitch to CV would be helpful - but are seldom done - if, ever done.

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by starthief » Wed May 20, 2020 8:43 pm

I'm playing with the Disting right now, trying to track a Hertz Donut through Natural Gate. The pitch tracking algo really wasn't doing very well, but the Logic algorithm set to XOR works surprisingly well for PLL purposes :D

Pitch to track into X
Oscillator that you want to follow into Y
XOR output into pitch input of that oscillator

Other logic types can also work to varying degrees, but XOR seems to be the best.

For this particular case it actually tracks better than my A-196.

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by wuff_miggler » Wed May 20, 2020 8:48 pm

^ thanks starthief! i still dont own a pitch to CV module, PLL (they're in a queue) - but i did order the Doepfer Dual Logic module last night - i am stoked i can try this with that!!

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by adaris » Wed May 20, 2020 10:09 pm

Would the Disting's pitch to CV algo potentially work better on the new EX?

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by JES » Wed May 20, 2020 10:56 pm

Disting’s clockable LFO worked better for me, not pitch to CV but pitch to waveform....
"Now, I'm off to hook my cat's litterbox up to an envelope follower." --Aragorn23

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by Jim the Oldbie » Wed May 20, 2020 11:33 pm

I've never used a Disting, but regarding the "idle pitch," would it be possible to use a sample & hold on the CV out, gated with either an envelope or gate out, whichever is provided?

Edit: Granted I'm just getting back into all this stuff after a long absence, but how have I missed this thing?? :hyper:

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by LDT » Thu May 21, 2020 12:04 am

It has been some years since I did pitch to cv. I had an MS20 as well as the ASys module, and MS20 was by far the best.
-Lars

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Re: Pitch to CV options

Post by Roge Piltoney » Fri May 22, 2020 9:47 am

starthief wrote:
Wed May 20, 2020 4:51 pm
Most pitch trackers are going to get weird when the input signal goes silent. Normally you'd also pair them with an envelope follower and a VCA to silence the mess (on the Disting, the algorithm includes an envelope follower).

Some modules track pitch for themselves, but don't produce CV:

- Tides
- Kermit
- Starling Via Sync and Sync3

An advantage these have, besides being self-contained, is they tend to keep going at their current frequency when the input signal is lost. Like tap tempo on an LFO, only faster.


An actual analog PLL, like the Doepfer A-196, is more open and flexible about how you use it but also more touchy and flaky about how it tracks. The flaws give it character though. :) Unfortunately its internal VCO doesn't track 1V/OCT, so if you tap the CV to drive something else you'll get bad results -- but you can instead patch it through an external oscillator, and not only will that one track, the CV signal that feeds it can be used for still more oscillators.

You can patch a PLL without a PLL module. You need something to act as a phase comparator (I've found an XOR logic gate tends to work best, and you can patch them with Maths or Cold Mac although it's tricky), preferably a slew (if I remember right, Maths can't also slew if you've patched it to do XOR), and an oscillator. And patience and luck. :)

Some cool info here! Thank you for the helpful response
Some questions though:
1. So Tides and Kermit and Sync just need an audio signal and they can produce their own wave in sync with it?
2. Regarding the PLL, what do you mean by "but you can instead patch it through an external oscillator"? Patch what, the CV out? But you said that doesn't track 1v/oct. Could you clarify?
3. I am certainly intrigued by the idea of rigging up a PLL from scratch. But could someone explain how XOR is comparable to a PLL?
JES wrote:
Wed May 20, 2020 10:56 pm
Disting’s clockable LFO worked better for me, not pitch to CV but pitch to waveform....
Sooooo, audio into clock input?

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by hinterlands303 » Fri May 22, 2020 10:01 am

Jim the Oldbie wrote:
Wed May 20, 2020 11:33 pm
I've never used a Disting, but regarding the "idle pitch," would it be possible to use a sample & hold on the CV out, gated with either an envelope or gate out, whichever is provided?

Edit: Granted I'm just getting back into all this stuff after a long absence, but how have I missed this thing?? :hyper:
Seems like you'd actually want a track and hold right? Gate on - it tracks pitch, gate off and it holds the last pitch.

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by Jim the Oldbie » Fri May 22, 2020 10:13 am

Yup, that's what I meant to say - gated, not triggered.

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Re: Pitch to CV options

Post by starthief » Fri May 22, 2020 11:01 am

Roge Piltoney wrote:
Fri May 22, 2020 9:47 am
1. So Tides and Kermit and Sync just need an audio signal and they can produce their own wave in sync with it?
Yep! They work pretty much like a clockable LFO, but at audio rates. So they oscillate at the same frequency -- or a multiple or division of the frequency -- as the input.

Roge Piltoney wrote:
Fri May 22, 2020 9:47 am
2. Regarding the PLL, what do you mean by "but you can instead patch it through an external oscillator"? Patch what, the CV out? But you said that doesn't track 1v/oct. Could you clarify?
3. I am certainly intrigued by the idea of rigging up a PLL from scratch. But could someone explain how XOR is comparable to a PLL?
How a PLL works, in a nutshell:

A phase comparator outputs a signal representing whether two signals match in phase. An XOR logic gate works pretty well for this: it outputs a low signal when its two inputs match in phase, and high when they don't.

So if you patch an input signal and a VCO output into the XOR inputs, and the XOR output (optionally through a lowpass filter) into the VCO's pitch input, it will cause the VCO to "speed up" and "slow down", adjusting very rapidly to match the input. It's not a true 1V/OCT signal but a constant "steering" to keep the oscillator in tune.

(In practice, the relative waveshapes of the input and the oscillator can cause it to lock to the wrong octave, or bounce rapidly between octaves... but it'll still be in tune.)


The Doepfer A-196 PLL has three sections: a VCO, a phase comparator section (three types, selectable with a switch) and a lowpass filter to smooth the phase comparator output. By itself, it can produce pulse waves that match the input frequency, with varying degrees of success depending on the input signal and the settings you choose.

Its VCO doesn't track 1V/OCT, so if you try to use that same "steering" signal to control an external oscillator, it'll be wrong. But you can bypass its internal oscillator entirely, and patch an external oscillator into the loop instead.

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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by ersatzplanet » Fri May 22, 2020 5:12 pm

The big question is do you need it to do that in realtime? If not, there are lots of software solutions that can be very accurate. Even the pitch to MIDI conversion in Ableton is not bad. That is one step away from CV. Of course it is targeting note generation and not the spaces between them. It can be polyphonic though, which is a plus. I have to admit that my experience with it is minimal, but it did a great job for me at the time.
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Re: Pitch to CV options (I know I know, but can it be DONE??)

Post by Roge Piltoney » Sat May 23, 2020 2:49 pm

ersatzplanet wrote:
Fri May 22, 2020 5:12 pm
The big question is do you need it to do that in realtime? If not, there are lots of software solutions that can be very accurate. Even the pitch to MIDI conversion in Ableton is not bad. That is one step away from CV. Of course it is targeting note generation and not the spaces between them. It can be polyphonic though, which is a plus. I have to admit that my experience with it is minimal, but it did a great job for me at the time.
Definitely needs to be in real time!

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Re: Pitch to CV options

Post by JES » Sun May 24, 2020 3:20 pm

Roge Piltoney wrote:
Fri May 22, 2020 9:47 am
JES wrote:
Wed May 20, 2020 10:56 pm
Disting’s clockable LFO worked better for me, not pitch to CV but pitch to waveform....
Sooooo, audio into clock input?
Yes, that’s it. Batumi is supposed to work well this way but I have never tried. If you want to get clever, audio into comparator, which gives you a square wave, into clock of LFO, is even more stable. You only get the waveforms the LFO gives you but some of the more interesting digital LFOs could give you a lot of options. Mono only, obviously.
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Re: Pitch to CV options

Post by Roge Piltoney » Mon May 25, 2020 2:51 pm

JES wrote:
Sun May 24, 2020 3:20 pm
Roge Piltoney wrote:
Fri May 22, 2020 9:47 am
JES wrote:
Wed May 20, 2020 10:56 pm
Disting’s clockable LFO worked better for me, not pitch to CV but pitch to waveform....
Sooooo, audio into clock input?
Yes, that’s it. Batumi is supposed to work well this way but I have never tried. If you want to get clever, audio into comparator, which gives you a square wave, into clock of LFO, is even more stable. You only get the waveforms the LFO gives you but some of the more interesting digital LFOs could give you a lot of options. Mono only, obviously.
Wow seems like a really good option! Thanks for the info.

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