MATRIXSYNTH

KORG Z1

images via this auction

via mibrilane in the comments of this post.

repeaterDS - demo #1

YouTube via clone45a6
"Nintendo DS homebrew sequencer from the maker of glitchDS"

"A more melodic demo of repeaterDS. Free homebrew software for the Nintendo DS."

Stereo T-Resonator Noodle #463

YouTube via bigcitymusic
"Here is the amazing, ingenious, save the world, Jomox T-Resonator with the Elektron Machinedrum SPS-1."

via this auction

"An extremely rare item to be found today: A/DA's Harmony Synthesizer. This is the holy grail of A/DA effects pedals and apparently in 1980 there were only 800 of these made retailing for $500.00 each! This effects pedal has been called 'Exquisitely rare'

Controls:
On rear of unit the following jacks: Control Pedal Switch, Effect Out, Mix Out, In

On top of unit: Knobs- Regeneration, Delay Only(25 ms > 200 ms), Harmony A(Coarse Tune, Fine Tune, Delay 12.5 ms > 100 ms), Harmony B(Coarse Tune, Fine Tune), Mix(Dry, Effect), Level; On/Off Click Switches- Regeneration, Delay Only/Harmony, Harmony A/B, Effect In/Out"

Roland GR-700

via this auction

"The GR-700 is a stomp-box guitar synth with the same synth engine as the JX-3P. Designed to be used with the G-707 Guitar controller"

Alesis Andromeda A6

images via this auction

KORG Polysix

via this auction

"Korg Polysix Motherboard / CPU KLM-367A"

Korg Z1 | demo (1 of 2) by syntezatory.prv.pl

YouTube via Jexus.

Warning: there is either a sick pig in these videos or it was mistreated, or both. If you are sensitive to that sort of thing, skip it. I always am sensitive myself. Not sure what's going on with it. As Eric Barbour of Metasonix might say, in this case it's definitely a SHIT PLANET!!!!
"1997 Korg Z-1. All sounds programmed by WC Olo Garb. Video editing by WC Olo Garb. ||| Syntezatory.prv.pl Videos: showing you not what a synthesizer can do, but what a man can do with a synthesizer.

Note that in some patches I use aftertouch (the force applied while depressing the keys as a modulation source) - that's why the sound changes even though it seems that nothing is really being done to the synth in terms of control."

Analog Tracking Generator - aka Control Voltage "Twister"

"The Oberheim Xpander contains a module called a 'Tracking Generator' that allows you to program a 5 section non-linear curve.

This is my attempt at implementing the idea in analog. It can be used to "twist" control voltage signals into various shapes, and has a 10 section curve.

The implementation makes us of the LM3914 bargraph chip with a high frequency 'dither' oscillator. The dither oscillator pulse width modulates the comparator outputs. When the PWM is integrated, it produces reasonably straight line segments between programable voltage points." click here for more.