Generating melodic sequences by treating time as probability

Moogul · Joined: May 02, 2023 Posts: 4 Location: Iowa City, USA

Inspired by a unique "probability controller" from 1974, which I found in the University of Iowa’s Electronic Music Studio, this video shows you how to create your own version using modern gear such as Make Noise’s 0-Ctrl (although ordinary sequencers will work too).
Detailed patch notes in the video:
https://youtu.be/c-n3v9blKSk

blue hell · Posted: Wed Mar 26, 2025 6:39 pm Post subject:

Right, it is audibly an interesting sequencer .. but i've learned not much from the video beyond that it sounded nice Shocked

Oh and that you'd need variable step duration., but .. it is a clocked system - right .. being CMOS I'd expect that ..so in what steps are durations changed . or is that analog ...

Then there is talk about the 'steps' can you still use that word? to represent notes, it seems suggested that a note is fixed to a step, but also that the scale can be changed ..that can not both be true? or how does that work ..

Did you have a look at the Klee Sequencer? And how is this different? There seemed to be an overlap in ideas, where the Klee might be a generalization ... or is my view distorted ...

Just a couple of examples of thangs that did not become clear to me . there probably will be more .. but .. schematics might help.

And it for sure makes nice sequences in the video Cool

Moogul · Joined: May 02, 2023 Posts: 4 Location: Iowa City, USA

Thanks for your feedback. First, you mentioned you’d need variable step duration, but actually you can do this trick with an ordinary sequencer: ie. by using an LFO to clock the sequencer and patching the sequencer’s second lane/channel (if it has one) back into the LFO’s frequency input.

Yes, it is a clocked system, but it’s using a digital logic counter.

Yes, each “step” on the PC is fixed to a note, and yes the scale can be changed. The scales sets the range between the first “step” and the 15th “step”. If the scale is 1.25V, then your steps will be exact semitones when sent to v/o input on the Moog. Increasing or decreasing the scale will allow it to play with alternative tuning standards, eg., Buchla’s 1.2 v/o.

The Klee Sequencer is completely different - it’s based on a digital shift register, with possibility of multiple active bits.