TX81Z Patch Degrader with Interpolation

This quick demo illustrates how TX81Z Patch Degrader is interpolating between previous and newly generated parameter values. TX81Z Patch Degrader is a Max for Live MIDI effect that chips away at patches on the TX81Z by randomly changing (or degrading) parameters at a specified rate. What makes the process interesting is that it is possible to ramp up or down (interpolate) to the new value rather than changing it instantaneously.

To create the Max for Live MIDI instrument I started with TX81Z Editor 1.0 by Jeroen Liebregts who was kind enough to share his work on maxforlive.com. I added in the degradation process features and made some adjustments to the interface to make room for the controls. Once I get things shaped up I’ll be happy to share the patch if anyone is interested.

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The features I added are visible in the second panel of the TX81Z Patch Degrader Max MIDI effect. I’ll describe them from the top down:

  1. Level bypass prevents the operator levels from being included in the degradation process so that the sound doesn’t completely die out.
  2. When the interpolate switch is on new values (as long as they have an adequate range) are ramped up or down to the new value based on the rate.
  3. Loop causes the degradation to continue indefinitely by reshuffling after all 73 parameters included have been degraded.
  4. Free/sync toggles between changing the parameters at an arbitrary pace set by rate, or note divisions based on the project’s tempo (therefore sync will only degrade while playing)
  5. Rate adjusts the rate of degradation when in free mode, and the time it takes to ramp up or down to new values when interpolate is on. Rate is milliseconds and ranges from 15ms to 2000ms.
  6. Below rate are the note durations for sync mode ranging from a 1/128th note up to a dotted whole note.
  7. Finally the degrade button starts the process while interrupt stops everything so when you hear something you like you can save the patch on the TX81Z.

The TX81Z has a fairly small buffer for MIDI values, so spraying values at it too quickly will generate the “MIDI Buffer Error”. However, even after getting the error it will continue listening to the incoming data, so even though it might be skipping a parameter here and there it lets me keep throwing things at it. The video below shows how the LCD display responds to the stream of values coming at the machine.

TX81Z Patch Degradation with Interpolation! #glitch #fmsynthesis

A video posted by John Keston (@jkeston) on

I’ve saved quite a few very interesting effects so far and have nearly run out of the 32 patch positions available on the unit. Perhaps the next step is to add a library feature especially since I’m not thrilled about the idea of saving patch banks to cassette!

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New Spectral Tablature Collaborations Exhibited in Tokyo

I am pleased to be participating in an exhibition of work by Jasio Stefanski at Print Gallery in Tokyo, Japan. Jasio is showing a variety of his work including two pieces that we collaborated on together fron the series Spectral Tablature. The first piece is Synthetic Skyline previously exhibited for the Audible Edge sound art exhibition at the Katherine Nash Gallery in Minneapolis. The second piece is a new work in the series titled Synthetic Transitions.

Synthetic Transitions

To create the work I started by composing a simple sequence of notes that speed up and then slow down. Jasio requested that we included diagonal lines in the piece so I used linear portamento on the Moog Sub 37 to create the “transitions” he was interested in seeing. The video shows the plotter rendering Jasio’s Reprise of the work shown/heard in the image/audio below.

Synthetic Transitions Reprise

Jasio’s Reprise is based on form and color values as opposed to acoustic accuracy. The visuals were composed to place emphasis on the “transitions” or portamento. The output visually reinterprets the angles informed by the gliding notes without connecting them in the composition. When sonified the plotted design singles out the portamento, isolating it from the context of the sustained frequencies.

New Spectral Tablature Collaboration

Spectral Tablature 2015

Part music, part visual art, and part sound design, the collaborative series Spectral Tablature is something I’ve been doing in various forms since 2013. Recently I have been working on a new piece in collaboration with Jasio Stefanski for an upcoming exhibition of his work. I’ll share more information about the exhibit in a future post. For now I’d like to present some of the content that I generated in the process of working on the project.

The image above is spectral analysis of a piece of music that I composed deliberately to produce interesting sonic and visual forms. The piece includes three layers of sequences that slowly speed up and vary in pitch and then slow down again. The speed of the sequence was based on an LFO with a variable rate rather than BPM. This process, along with other techniques, resulted in a form that starts simple, approaches entropy, and then returns to its original simplicity.

Example with Portamento

The final piece will be reprocessed visually through a set of design criteria determined by Jasio. Once the new design has been printed I will digitize the image and reprocess it as sound. The new audio will retain the original frequencies and temporal information but the textural and timbral qualities will be completely transformed.

Duet No.7 for Synthesizer and The Singing Ringing Tree

This is the last of seven videos produced documenting my five day recording session and performance series at the Singing Ringing Tree (SRT) in Burnley, UK. There’s a lot more content in the can, but for now this is enough to represent the project. My part of the collaboration with the SRT was simultaneously recorded on site using a Novation Bass Station II connected to a USB battery. I also ran the Bass Station II through a Moog Minifooger Delay.

My last day on site was also the windiest and it turned out that the best wind reduction happened to be a very thin cotton t-shirt wrapped around the binaural head as you can see in the photo below. The strong winds, although useful, made the process quite difficult, and the binaural effect seemed a little less prominent with any sort of wind reduction applied. However, I was able to get couple of good takes by carefully placing the dummy head next to the SRT and opposite the wind. Please checkout the playlist of all six duets (#2 was omitted) on my YouTube channel.

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Duet No.6 for Synthesizer and The Singing Ringing Tree

This is the sixth of seven videos produced so far documenting my five day recording session and performance series at the Singing Ringing Tree (SRT) in Burnley, UK. I performed accompaniment for the SRT binaural recordings simultaneously using a Novation Bass Station II connected to a USB battery. I also ran the Bass Station II through a Moog Minifooger Delay.

This piece was yet another captured during my third day on site. I chose to include this one to emphasize the potential for serendipity in compositions like these. About forty-five seconds into the piece you will notice the sound of a small, prop-driven, perhaps single engine plane flying overhead. Ironically the drone I was making was slowly modulating the pitch like an air-raid siren. Clearly hearing the aircraft in my headphones led me to slowly and deliberately morph the drone into a sound mimicking its engine.

NOTE: This is a binaural recording combined with a monophonic synthesizer track. Although it sounds great through speakers, circumaural headphones must be used to experience the binaural effect.