Monday, July 02, 2007

ah, sweet edification

I've been spending spare minutes with these new modules every chance I get and two in particular had me stumped on their internal operation. It's funny that I would discover the mystery of these two on the same day, both by accident.

The Plan B Heisenberg Generator and the Livewire Dual Cyclotron have been the proverbial enigma for me; the Dual Cyclotron particularly more than the Heisenberg. The Heisenberg I actually had pretty well figured out except for the relationship between the two "halves"; particularly the "Chaos" knob on the smoothed output half. The Dual Cyclotron I had basically no solid idea on...I mean, I kinda did, I could obviously hear how things changed, but I had no idea specifically what the various knobs actually did. Just turing knobs blindly is fun, but eventually you want to know what you're certainly makes recalling a cool sound a lot easier.

As I said, the Hesienberg wasn't that much of a mystery. The various knobs all have specific names which are very descriptive of their function. Mean, Deviation, CV control of these, etc. However, what I was confused about was the Chaos control, which, based on it's location, solely effected the Smooth (slew limited) random output half. What seemed very odd was that with Chaos set to 0, the Smooth output voltage did not seem to change at all; with the Chaos up high (2 o'clock +) the output voltage would be very erratic, "Chaos" even. ;)

Still, I couldn't tell exactly what it was doing. It seemed like Chaos controlled additional modulation of the sample and hold already clocked by the "Meter" knob at the bottom of the module, but then again, sometimes changing the "Meter" knob did not seem to alter the Smoothed output. Until today, I just chalked this behavior up to an "endearing quirkiness" of the module. While showing the product page to a colleague at work, I noticed a link to a block diagram of the module and how it integrates its Atmel 2051 Micro Controller. Of the 20 or so times I had studied this page before I bought the module, I never noticed this. It clearly indicates that the "Chaos" knob is the control for the LFO/Clock controlling the sample and hold for the Smooth output. It's basically the "Meter" knob's equivalent on the Smooth output half. Simple. :P

The Dual Cyclotron, however, was much more elusive. It has virtually no documentation, er, actually no documentation. The creative description of the module as a design taken from the Roswell spaceship crash wreckage is cute and adds some general character to the coolness of the thing, but it's far from helpful on indicating how the hell it does the cool shit it does.

As far as I got to figuring thing out was that there are 3 separate oscillators, two identical ones (presumably the "cyclotrons" and a 3rd oscillator which seemed to be the primary voltage output source. All 3 had "Symmetry" controls, just like the Vulcan Modulator, so I figured they did the same as on the Vulcan which is shift the positive peak of the waveform to either side of the center Y axis (like a pulse width, but for any waveform). It sounded like it did that too. The two cyclotrons each had speed range controls (selectable knob for "Stretched, Normal, and Compressed") and the main oscillator had a switch for LF (low freq) and AF (audio freq). Everything else I only had a vague idea on, and as I found out today, almost the completely wrong idea.

No less than 10 minutes after discovering the block diagram for the Heisenberg, I'm in the bathroom and notice an old copy of Electronic Musician which had a feature on analog modular synths by Gino Robair (June 2006). I had read this article before, but it was certainly more interesting than the dozen other articles in the magazines I have read multiple times in the bathroom. Low and behold, what do I find but a perfect and simple description of what each control on the Dual Cyclotron does!

It's a lot of info, and I understand the module a lot more now, so I want to save it for the video demo. Now I'm confident it's gonna be a good one. :D

1 comment:

Zerosum said...

That was an amusing read:D

I think Gino also did that sample on the metasonix front page