Trick for ratcheting CV/Gate

[panelist]

Not sure if anyone else has come up with or shared this recipe, but I just figured out this trick to do ratcheting on an external synth via CV/gate and I figured other people would get some use from it. It’s a twist on the standard CV/Gate pair where you replace the gate channel with a VALUE LIN channel and “fake” the gate pulse using a square wave LFO. The main downside is that you lose the ability to set note length, but if you’re doing anything with ratcheting you’re likely using short note durations anyway.

Take your normal gate channel and change it to LIN
On the LFO page for the channel set:
• SPD to 63
• MUL to x16
• WAV to SQR
• MOD to ONE
• DST to VAL
• DEP to 127

This makes it so that a 1/16th note square wave pulse is sent every time a note is triggered (1/32nd high, 1/32nd low).

Now, enter steps in record mode like you normally would, but to get a step to “ratchet” you need to P-Lock the LFO MOD to TRG and LFO MUL to whatever rate you want for the ratchet. You can also mess with LFO SPD to get odd ratchet values.

[avantronica]

Not trying to steal your thunder, but I thought i’d shared the technique before but described how you could retain note length info and ratchet

anyway, along these lines

CVA Pitch
CVB Value Lin

ENV1 to Value Lin B Value
LFO1 to ENV1 Sustain

Set ENV1 to be a resetting (with dot) analog style gate shape, so it will record note duration, but set 0 for time domain components and set sustain to max

Set the LFO to Trig and Phase to taste (Speed 32 allows tempo related effects and fine tuning each way into triplets etc)

P-Lock the LFO depth to minus -128 for the steps where you want to ratchet
P-Lock the rates for all the ratchet fun

It helps when you have a snappy envelope on the receiving device to hear the ratcheting

[panelist]

No thunder stolen! I did some searching but couldn’t find anything so I put up out the idea. Always good to compare notes!

Mods, feel free to merge threads

[avantronica]

@avantronica

along these lines

Somebody asked for clarification on this post

When i followed it through it gave a strange response when followed close to the letter - the strangeness is a bizarre internal ringing which sets up a sinusoidal oscillation (no lfos were sinusoidal) which happens during the first ratchet - this is due to it seeking to address the sustain level whilst the sustain level is being ‘built’ (the envelope is not infinitely quick at forming, and it’s not directly analogue

Anyway, it made it obvious then that targeting the Env Depth was what was required as opposed to Env sustain level - they’re basically interchangeable if you think of a gate style envelope (the quote above was anecdotal anyway, i.e. a recollection of the original post)

so to get something like as follows, set as described below

This will allow a pair of CV outs to control pitch and gate, but the LFO depth can be parameter locked within a step to bring in some ‘carving out’ of the gate to depth to leave some ratchet-gates … it’s periodically killing the ENV1 Depth A which is itself targeting the CVB value … by having the LFO tempo matched and set to retrigger on Trig it means the first ratcheted gate starts high (with the lfo phase in the right position)

CV track

CV A is pitch V/oct for most users

CV B is Value Lin (ensure that the VAL of Value Lin is dialled back to zero when you click the osc 2 page - not when setting up CVB whilst using Fn though, you should see one dial amidst 4 greyed out controls, you need to turn Enc C to zero it out, it defaults to an offset) when setting up CVB set lower value to 0V and upper to 5V to begin with

ENV1 is set with 0 for A D R and Sustain to Max
DestinationA of the env is CV B value

This arrangement basically mirrors what the inbuilt Gate mode does

For LFO 1 the settings are discussed above
set mode to Trig
try multiples of speed 32
pick a square wave for short gates

Use a high positive depth for setting ratcheting as it allows the default phase of the lfo to start the gate carving with an ratchet active at key press - the negative phase of the lfo will soon carve out the voltage which is clamped between 0 and 5v

So essentially, you can record in a natural playing of varying step lengths - then if you go to the steps you want to ratchet you p-lock the LFO depth high

so it looks as follows on the oscilloscope