Friday, 29 March 2013

Cellular Automata Sequencer (panel 9)

This is a sequencer based on cellular automata (CA) rules 90 and 150. A panel contains 6 neighbourhoods, each neighbourhood has 4 cells, with cell #2 being the boss.

This description might get very complex very quickly so just scroll down to look at the block diagram and panel layout if that helps.

Each neighbourhood is independent but they may be patched together as the you like to get a 24 stage sequencer or used as 6 individual 4 stage sequencers or anything in-between.

Each cell has its own gate output so can be used to animate the left or right input of any other neighbourhood. It means multiple sequences can be set up to be running in parallel off the same clock (or off different clocks if desired).

Each cell also has a pot to give a variable voltage. The voltages for the 4 cells of each neighbourhood are summed and these can be chained across all neighbourhoods using the CV inputs or the negative CV inputs. Each neighbourhood also gives a 'random' CV, not true random but good luck trying to work out what it is doing. this 'random' CV could be chained with CV signals from other neighbourhoods as well.

The logic chips in each neighbourhood can be changed to conform to different CA rules, although XOR seem to give the best results. If one neighbourhood has an XNOR chip it could be used as the 'seed' neighbourhood to animate the others, rather than using external signals.

Build manual (includes schematic) is HERE 1.3Mb
User Guide is HERE (pdf 800kb)
See THIS POST to buy panels and build your own.

Monday, 25 March 2013

neurotic panel (5)


Two discrete ADSRs based on the Aries design with added End out to re-trigger or get the 2 modules to trigger each other.

CV processor, two inputs are hardwired to the outputs of the ADSRs plus two external inputs.

Conjoined Transient Generators, one is a stand-alone TG the other is separately controlled by a gate but will only work if the main circuit is operating....a bit like Kuato in Total Recall.

Two chaos circuits (Jerk-off), these will be built so one cycles very slowly the other will be at audio rates.

Four Neurons

A three stage Transient Generator, never really seen anything like this!

User manual is here (pdf - 470kb)

Friday, 22 March 2013

Drum Panel (8)

update -
20nov2013 dropped the dual DC mixer, panel is being manufactured now

1. envelope follower, that can also be used as an AR generator

2. two LFOs, triangle and square outputs

3. a drum machine based on the analogue board of the DR-55, each sound can be individually triggered, bass and rimshot can be tuned with pots.

4. two drum modules, these use envelope followers, crude VCOs and VCAs, so can simply be used as VCOs as well. These are based on designs published in an old Japanese magazine article, I heard these demonstrated by Under Techno Systems at a Tokyo synth meet back in 2004 and never forgot how fantastic they sound. They have been changed a lot from the original design but the basic circuit blocks are the same.

5. Quadrature Oscillator (QUO) / Low Pass Filter (LPF) with chaotic feedback. It can be switched to perform as a very low freq QUO, quadrature VCO, LPF with Q and a pot allows non-linear resonant feedback to obtain richer and irregular harmonics.

6. two VCAs / Ring Modulators (RM), a pot is used to set it in VCA or RM mode. If the pot is set in the middle you can have a hybrid of both. This is based on the design in the EMS Synthi-E with some mods to suit +/-12V systems and use modern ICs.

7. Difference Rectifier, luxury version with LEDs!

8. twin-T VCF with LDR resonance circuit & VC Clipper (somewhere between a VCA and a timbre modulator)

 dual EMS Synthi_E VCA/Ring Mod & deluxe Difference Rectifier

 Dr Go-go (Dr-55 clone)
 Envelope Follower, dual LFO
Car-crash VCF, VC Clipper (wave-shaper), dual EMS Synthi_E VCA/Ring Mod & deluxe Difference Rectifier