I bought an Octatrack MK1 last week. I’m still very green with it. Slowly working through Merlin’s pdf to get to grips with the basics. I’m trying to figure how I’d record and manipulate CV from my eurocrack.
Basically, I want to record the triggers from a bouncing ball patch, then time-stretch them so they’re quantised with my clock.
I’ve read a few posts on recording, but couldn’t find anything about recording control voltages. It would be a really powerful tool to be able to take a very organic, off-grid sequence and manipulate it so it fits rhythmically.
Hmmm interesting question. You could record it as audio and then slice and quantise that way - then send back out as quantised triggers to your rack.
I’ve used a modular pulse to clock Eurorack sequencers out of the OT outputs so it can be loud enough (at least for +5v sequencers may struggle with sequencers requiring a louder signal)
Should work in theory, but not done it myself. But I have used a modular pulse taken from a Make Noise René as a sample to then send back out so should work fine.
As your first project it’s fairly straightforward, but it is the OT so not always immediately intuitive necessarily.
But record audio, which has QREC set correctly so it records at the tempo you are working at and at the start of the bar.
The ‘complex’ part is that you will slice and then have to remap the slices to match the rhythm of the bouncing ball audio before then quantising them afterwards. It’s quite a usual use of slices and a bit awkward.
But the way I’d do is record it - assign the recording to two tracks - one which plays the raw audio, and then another which you slice and match the timing of the raw audio then once close enough; mute the raw audio and tighten up the timing of the sliced version to a metronome
I only skimmed the cuckoo video but it looks like he’s doing audio rate modulation which is cool. But to do slower cv rate recording you would need to have dc coupled inputs which I don’t think the OT has. Otherwise a basic technique for CV to audio and back is a sine oscillator into a VCA getting controlled by the CV you want to record. Record that signal into the OT. Feed the output into an envelope follower to reconstruct the control voltage.
I’m going to dive into this once I’ve got the kids to bed.
It’s my first delve into the OT so I’ll probably be back with confused/whiny/frustrated questions.
I’ve been trying to get the bouncing ball to fit the grid whilst keeping its organic exponential curves for some time. I think Second Woman use this a lot.
So I’m halfway to getting it to work. Sampled the CV as audio and used it to trigger an LPG. It works, but it’s far from perfect. Had to up the sample rate. I think I need to play around a bit more with the input gain. The signal is a dirty version of original and has some strange zero crossings that don’t match my scope. In fact it looks very different after going through the DAC. The initial trigger seems quiet compared to the fast repetitive triggers at the end on the sample.
Slicing the CV and fitting it to the grid is getting close to the results i wanted. I can see being able to manipulate chaotic CV this way will be very fruitful.
I’m going to try @dragonaut suggestion of modulating a sine wave and then reconstructing with an envelope follower next.
Really nice first project to cut my teeth on the OT.
Maybe the faster ones at the end are closer to low audio rate so they’re passing through while the slower ones at the beginning are too slow to make it through the dc filtering cleanly.