This is a study for a performance I'll be doing in a few hours, at the 2025 PRFBBQ. This is all Max/MSP, using the Jaap-Vink-inspired feedback patch I've been working on for a while. To the Jaap Vink topology, I've added another ring modulator (on the output), another delay, high- and low-pass filters, two pitch shifters (one inline, one on output), convolution reverb, and yet another delay on the output. I've also made this into four channels, so it can be an arrangement of feedback. That's a lot of controls. Let's see how it goes.

This one doesn't use all of those filtering options, but it's both one of the shorter and more engaging of the studies.

The title comes from the IBM 602 Calculating Punch.

Not technically a late submission for this year--I'm in before the deadline of midnight Eastern. Why so late? I was out of town to play a show for the solstice, and a tight travel schedule meant I couldn't finalize the recording until late Sunday night.

The sound source here is a Max/MSP patch I've been developing based on the feedback patch Jaap Vink developed at the Institute of Sonology in the 1970s. This Max patch is four channels of ring modulator > delay > ring mod > delay > level setter > low-pass filter > high-pass filter > reverb algorithm > graphic EQ (global) > back to the input ring modulator. In this case, there's no explicit input to the feedback loop, apart from clicks when values are set.

The sound and structure are a performance simply from changing the values of all these settings once the patch starts feeding back. It's a work in progress, but it's promising.

The title comes from the fact that 599 (the number of this weekly piece) is a twin prime with 601.