MATRIXSYNTH

The Ultimate Filter List

Title link takes you to the largest list of filters I've seen to date on one site. There's info and images on each. via sequencer.de.

Akai MFC42

Circuit Bent Sega

Title link takes you there. This one sent in via Gijs who brought us this Casio SK-1.

MIDI Resources

No title link. Just the following three links sent into AH by Chris Strellis. If you know of more, feel free to comment. Bookmarking these for a rainy day.

http://253.ccarh.org/handout/controllers/
http://www.tweakheadz.com/midi_controllers.htm
http://www.soundonsound.com/sos/1995_articles/oct95/midibasics3.html

One Hell of a Knob

flickr by heckadecimal.

Roland TR-707

Title link takes you to more gear shots.

Roland SH-7

Title link takes you to shots pulled via this auction.

Sequential Circuits Prophet 5

Title link takes you to shots pulled via this auction.

Title link takes you to a couple of shots pulled via this auction. The auction states it's an FM synth, but my understanding is it is a Wavetable, vector synth like the Sequential Circuits Prophet VS and Korg Wavestation line of synths. I believe the people that worked on the Prophet VS spent a short time at Yamaha after SCI went under, followed by Korg. If you know more, feel free to comment. It's been a while since I read the full story. The Yamaha TG33 is fully digital.

Update via the world of next tuesday in the comments:
"It's a vector synth but the twist is two of the four waves are ROM and the other two are 2 Operator FM, so while it's arguably one of Yamaha's most minimal FM implementations, it does contain FM sounds. It has preset envelopes going on the FM if I recall. There isn't even a digital filter (like the Wavestation), so the FM capability helps fill the void a bit in terms of controlling brightness in timbre. Anyway, as with most Yamaha gear you can download a PDF manual to see what it has in terms of features."

ARP Quartet

Title link takes you to shots pulled via this auction.

Details:
"The Quartet is a 49 note polyphony keyboard with 4 main oscillators (Brass, Strings, Organ, Piano). Each sound can be played individually or grouped in pairs for different sounds. The String sounds are similar to the other ARP models, with this model being more affordable then the rest. One LFO is included, a low pass filter and attack / sustain control. All sounds are controlled by color coded switches (all present and accounted for)."