Wednesday, 31 October 2012

new chaos circuit

Playing around with a new type of chaos circuit. It is an extension of the Muthuswamy/Chua 3 component chaos circuit (which has just an inductor, capacitor and a memristor). In this one I developed a circuit to mimic a complex memristive system. Whether it makes it into a synth module or not is uncertain, it needs five AD633s at $8 each. For now it is just some good pictures.


Friday, 26 October 2012

update from post on 28/4/2012:
 A utility PCB, no pots, just jacks. Moog fixed filters - brass, vibes, humana, funk, harpsichord another fixed parallel BP voice filter (called gargle).
 These can of course be used with any audio or noise source but are intended primarily as filters for the extra outputs on the Veena.

 Also has white noise, pink noise, random vibrato, slow random, chunder (roar), two difference rectifiers and a 4046 phase locked loop circuit.

 Somewhat pleased to find everything worked very nicely. I tweaked a couple of resistor values to get the white noise level off the rails and get the LED brighter and flashing more often. Otherwise it is fine.

One nice feature is to daisy chain the filters to get new sounds.
The 4046 PLL was a bit of a gamble but it sounds great, adds a bit of distortion and spits, screams and fizzes as it tries to track the incoming signal. I built the proto-type with nearly all ceramic caps, figuring that will be the worst it can sound, but it actually sounds good. the original Moog passive filters, that these are based on, were likely built with ceramics anyway.

Monday, 15 October 2012

Filter Panel

This one has
"it's 555..." resonator/drone/noise source with CV control of pulse width for all five stages (plus a CV all input)

"Bleeding Gates" VC Slew: double module each has three individual channels giving 6 in all.

"Double Jerkoff" two chaos generators based on Sprott's jerk circuit. Each has X, Y & Z outputs and inputs. the input signal can be used to get the outputs to sync (when it feels like it) with everything else

"Spam filter" transistor ladder VCF

VCF - filter based on Arp and Electronotes designs.

"Divine CMOS" sub-oscillator, harmonic divider/mixer, harmonic ring-modulator, pattern generator, sequencer....

The user manual can be found  HERE

 These bottom three vids are by Jono

Monday, 24 September 2012

CMOS panel


Ready to be shipped, these cost US$1200 btw, 6 left Contains Great Divide, 8 bit Cipher, 4X4 Logic, 4 stage sample & hold, 4 stage thru & hold, 2 Bi-directional switches, CMOSC - 12 oscillator drone module.
The user manual can be found HERE.
If you want to see some up-close shots of the panel and PCBs, have a look at this PDF





Friday, 14 September 2012

ARSEq

A new circuit to go into panel #7
blurb (from http://www.sdiy.org/pinky/data/arseq.html) - This circuit is quite simple but an excellent envelope generator.
It has a counter, four attack release generators (ARgen) and a mixer.
It was originally intended to be a sequencer with controllable slew on each stage,
but it only took an extra pot and two diodes on each stage to turn it into what it is now.
The ARgen circuit is pretty common, I have seen at least 6 variations of the circuit around the net.
Most likely it evolved from the old diode function generators of analogue computer days.

Each stage takes two clock signals, the 1st starts the attack slope.
If the slope is steep enough the output will reach the sustain value set by the level pot for that stage.
The next clock signal puts that stage into release mode and the output starts to drop.
The 3rd clock signal starts the attack on the next stage, if the previous is still 'releasing'
the signals from each stage will sum in the output mixer.

LEDs indicate the envelope of each stage, so more than one LED may be lit at once,
indicating the output signal is a mix of two or maybe more stages.