furious recording technologies



FracSID module

A uCApps midibox SID, built in a 3U frac-rack modular synth panel.  All the power of the midibox SID, with 6 routable analog CV inputs, two gate outputs, and 8 analog CV outputs.  Since the midibox OS is open source, you can write your own apps for it, and turn it into a CV I/O beast!  Here are some behind the scenes details.






Furious LFCO (Low Frequency Chaotic Oscillator)

The hallmarks of simple chaos are all beautifully expressed in this custom, single frac unit module.  This module solves an ordinary third order differential equation, and outputs its solution, and its first and second derivatives.  The equation has a simple nonlinear term, which sends the oscillator into chaos!  You get three outputs that are nominally 90 degrees out of phase, and have complex harmonics that are dependent on the front "freak" (freq.) knob setting.  Since this knob varies frequency, amplitude, and the general level of chaos, I called it “freak”.  Also included is a DC offset that is added to the outputs so that you may sweep the three CV's together.  I should have added an external CV offset input – easy to add if you have space on the panel.  The circuit is based on one of the many, fantastic publications of J.C. Sprodtt.


Here is a good webpage summary of a similar circuit.  Here is a screenshot of the schematic. And last,  the Eagle PCB layout file as requested.


The module in the picture was my first attempt at etching a board.  I used the iron on / transparency method.  It pretty much failed, so I went back to protoboard and got it working.


Here is a video showing a Lissajous pattern made from the x and x-dot outputs.  The audio is of the x and x-dot-dot outputs modulating a lowpass and bandpass filter respectively, while the x-dot (first derivative) mods the PW of a square-wave. The freak knob is adjusted from low to high, then I used the offset knob to sweep the filters/PW.  Not a great sounding patch, I kept it really simple so that you can understand what you’re hearing, and the video gives a really good feel for what the circuit is doing.


Here is another, more entertaining video (got the hang of my cheap-ass video editing software).  In this one, X is modulating a CGS Bi-N-Tic filter, X-dot-dot is modulating a Blacet StonZ phaser, and X-dot is modulating the mix of these two sources.  A Bleep Labs Thingamagoop is hanging out, communicating on some primal level with the oscilloscope.  Unfortunately, his squelches aren’t audible this time - he’s just there to look ultra-cool.



Furious Stick


A simple, nearly completely passive component joystick.  Wiard’s joystick is the only frac-rack format joystick module out there that I know of.  It seems to be designed for use with the model 1211 “Joystick Axis Generator”, and unless you really want 0-10V it will require something along the lines of the Blacet Mixer Processor in order to tailor the output to your application.   That said, it looks nice, and I really like the inclusion of a trigger button. 


I found reasonably cheap and nice joysticks at Bent-Tronics.com and decided to build my own joystick module.  I was originally going to “clone” the mixer-processor circuit for use with a joystick when I realized that I could what I wanted with a bunch of pots wired properly.  The schematic is almost too simple to draw… for each direction you have two pots wired to each give 0-10V, and the wipers from these are wired to the CW and CCW terminals of the joystick pot.  I ran the output of the joystick pot through a follower just in case I connect it to something that has a low input impedance that could screw with the pot’s functionality (probably unnecessary).  Here is its backside.


The x-range is covered by the two pots on the lower right, and the y-range is covered by the two left side pots.  Left, right, up, and down are all connected to the corresponding pot.  If you want an inverted joystick y-axis, just turn the upper left pot all the way down, and the one beneath it all the way up.  Incredibly simple, and exactly what I was looking for.  Set the max and min settings while listening to the sound, and you’re good to go – offsets are taken care of naturally.






Furious AM Noise


I wanted some noise other than white, pink, or brown, and with a character of its own, so I bought a $0.25 AM transistor radio and frac-racked it.  Only thing that made this more difficult than it should have been is cutting a slot in a PAIA 1U panel… dremel tool joy.  Also, the speaker circuit was floating at 9V… which was kind of weird, so I had to A/C couple the output.  Using poorly received Mexican radio station noise to modulate a sawtooth via a ring modulator results in some really beautiful other-worldly sounds.  Here is an MP3 sample of AM radio (CNN) through a ring modulator, with some standard substractive synthesis mixed in via my new joystick (above).

Furious acoustic amplifier, model 723.1b

Based upon the research of Dr. Robert Hickling, this acoustic amplifier has been used to make critical field recordings to aid in the near field recording and detection of bollworm-infested bolls. This particular model has been custom fitted for use with the sensitive Core Sound binaural microphones .Stridulation Sounds of Black Fire Ants $9.95 *SOLD*





Furious contact microphone

Made from stock Radio-Schlock parts - a simple design, easy to implement.   BUILD YOUR OWN

 Furious monkeysynth model 32.21.330 rev. C

Fifty year old children's toy with cymbals replaced with contact microphones, and a microphone shoved up his a$$.  A beat-box from hell - quite temperamental. 





Grason Stadler 700 Shock Generator / "Rack candy"

1960's rack mount shock therapy device with the dreaded "Scrambler" setting that makes wonderful mechanical noise as a rotor clicks between multiple contact points to make your electroshock therapy session all that more painful.  Serious fetish item.  Looks great in a rack with my Blacet / Paia / CGS DIY modular synth!


Coming Soon (well... when I get the time.)

Furious VCCO (voltage controlled chaotic oscillator)

Nominally the same circuit as the LFCO, but with caps chosen for audible frequencies, and a voltage controlled input.  Here is a sample .wav of what it may end up sounding like.







Tektronix 5440 Oscilloscope

Bought it for $10 at a weekend swap meet.  I include it here to point out that the old 5000 series rack mount scopes are ideal for use with modular synthesizers.   It's 3 rack units high, so snuggles up nicely with many modular synths.  Plug-in modules for this scope run $10-$50 on eBay!  Only problem is that it is a bit deep - a couple of feet - it won't fit in some modular synth racks.  Also a good choice is the TM500 series - the modules include DMM's, frequency generators, counter-timers, and cute as hell little 2U oscilloscopes.  I have a little 1U TM500 mainframe and a counter timer that is real handy for oscillator tuning.