Modular Diary – 014

One of the recent guests on Darwin Grosse’s Art + Music + Technology podcast was E-Mu Systems Dave Rossum. Along with tracing the beginnings of the E-Mu Modular he also mentions the modular sequencer developed for the system. The idea of a sequencer broken into smaller component modules intrigued me, but I haven’t been able to find much information on it on the web.

What I did find was a video of Benge demonstrating it.

Benge also provides a grand tour of basic sequencer techniques demonstrated on Moog, ARP, Roland, Serge, and Buchla modular systems, as well as a little diversion with the VCS3.

Following up on Benge’s sequences I came across this thorough demonstration of classic Berlin School sequencing with a Doepfer MAQ16/3 and a Q960 (a recreation of the Moog 960).

While Benge uses a quantizer after the 960 Martin Peters tunes his sequencers by ear/hand – and that’s the possibilty that intrigues me. Hand (micro)tunings, and the possibility of setting up special tunings for a sequence without having to account for a complete system as one would be inclined to when thinking in terms of a keyboard.

Modular Diary – 013

A quick look at a few hardware sequencers that I’ve come across during the last few months:

Starting off with Mylar Melodies’ wonderful tour of the Intellijel Metropolis. (And Robert Syrett’s Audulus recreation of it.)

A step back to classic analogue sequencing (in a modern form) with the Doepfer MAQ16/3.

The Korg SQ-10, another classic given modern form as the Korg SQ-1 (here coupled with the Make Noise O-Coast).

Aphex Twin’s Cirklon.

And a step out of linear time with the Make Noise René.

Modular Diary – 012

With Audulus, as with most modular systems, the sequencer ‘control voltages’ are typically quantized before being passed on to an oscillator. I was keen to try out tunings with pure ratios and at first thought of piecing together a just intonation quantizer. However, since the sequencer knobs are fluid, it occurred to me that I could simply put together a small collection of ratio modules and connect them freely to the knobs. In this way some steps might be purely tuned while others could be set empirically.

The modules have an inbuilt reference pitch of 440Hz – that means that the 3:2 ratio will produce a pitch a perfect fifth above 440Hz. If the input is connected to a keyboard (or other) source the ratio will take that input as it’s starting point. The modules can be strung together so that the output of the 3:2 module can be connected to the input of a 9:8 module for example – producing a just second above the pure fifth.

Here’s an Audulus patch (very much a tryout, with the inclusion of all kinds of other bits and pieces I was experimenting with) demonstrating the approach.

Audulus Basic Sequencer Tryout

Modular Diary – 011

The arpeggiator of the Model 15 App is a step into getting an idea of how early analogue sequencers were set up: A voltage control knob for each step of the pattern. For pitch those voltages would typically be passed through a quantizer before being routed to an oscillator, but they might just as well be used to control velocity or filter cutoff, for example, perhaps with a parallel row for controlling gate times.1 It’s quite a different world from the piano roll visualizations one is accustomed to with DAWs, and encourages a different way of thinking – a different approach to creating and using sequences.

When I first started using Audulus I was somewhat puzzled by some of the sequencer modules included with it. I’ve since come to better understand (and appreciate) the old analogue models on which they are based. The great thing with Audulus is that all knobs can be linked to any other form of control – that means that the knob for each sequence step can potentially be controlled by an LFO or Random generator, to pick two examples. The sequencer can not only send out a set of control signals, but also be modulated itself.

  1. The Korg SQ-10 is a good example. Here’s a video with the SQ-10 controlling the MS-20 filters. 

Modular Diary – 010

Perhaps the most interesting aspect of the Richard D. James interview is his approach to tunings – thinking back over the Aphex Twin catalogue it becomes clear just how much they are an integral part of his sound(s). I was especially intrigued by his mixing systemised tuning with notes that are empirically chosen. And his thoughts on how sequencer patterns can can evolve when combined with custom tuning set-ups.

I’m still surprised by the extent that the modular world, having largely emancipated itself from keyboard thinking, seems to largely stick to equal temperament with it’s quantizers. Perhaps there’s been a greater focus on timbre, and the there’s the challenge of keeping voltage controlled oscillators in tune over a wide range, but as is clear with Aphex Twin, timbre and tuning are related.

Individual oscillators can of course be tuned exactly as one wants to. I experimented a little with the Moog Model 15 App, with the tooltip coming in handy when trying to nail pure intervals between the two oscillators. It’s also possible to set up equal distance scales (with divisions other than twelve) by attenuating the keyboard/input voltage.1 Arpeggiator pitches are quantized but it is possibile to use the fluid velocity output to control the pitch of the oscillators – the only catch is that one can’t zoom in on the arpeggiator controls as one can with the modules.

  1. Moog includes a 15 note EDO microtonal organ preset that does this.