Roland SH-09 (mod)
The Roland SH-09 was long the synthesizer in the worst shape in our collection.
After being transported to our Moog concert, it became completely unusable
(the pitch CV varied at random, usually about three semitones too low),
forcing us to restore it, so now it's in rather good shape again. 
Still, even before we fixed its various flaws, it was
worth a lot more to us than we payed for it (and its companion the Slumpler).
The SH-09 is the direct ancestor of the SH-101, and there are a lot of similarities. However, the 09 looks much more serious and lab-wise than the colourful plastic clown SH-101. Like its successor, it's a 1 VCO, 1 filter, 1 envelope, 1 LFO synthesizer, organized as follows:
The Oscillator has an octave switch for 32' - 2', a slider for LFO amount and a selector for sawtooth, PW, square wave or noise. You cannot blend the different waveforms, even though it's said you can put the selector in an unstable position between two modes and thereby get a mix of two signals (we haven't managed to do this and we don't care much actually). In PW mode, the pulse width can be varied manually, by the LFO or by the Envelope. The signal can be mixed with a suboscillator (square or pulse wave, one or two octaves down) and an external audio signal.
The filter offers settings for cutoff frequency, resonance, LFO- and envelope mod amount. The latter can be positive or negative or be replaced by the signal from a built-in envelope follower applied to the incoming external audio signal. Key tracking is always 100%, which is a shame. The ADSR envelope has single/multi trig or LFO trig, and a gate/env switch is provided for the VCA. The LFO has sine, square or random waveforms and a delay slider that is only active when sine wave is selected.
A rudimentary performance section contains a pitch bend lever, controlling pitch and/or cutoff frequency, by adjustable amounts. Portamento time is set with a knob, with no "auto/legato" option.
If this were all, the SH-09 would only be an inferior version of the SH-101 (albeit with better filter envelope options and LFO delay). However, our 09 is modified by its former owner, the splendid Peter Jubel (vocoder designer, DSP programmer for Clavia and Propellerheads, etc.). To our best knowledge, there are three modifications:
1) Turbo switch for the LFO. A little switch moves the frequency range of the LFO up into the audio range, providing a lot of interesting and bizarre FM effects. This is extremely useful and immediately makes the SH-09 to an excellent special effects device!
2) Feedback switch. An old trick from the MiniMoog days is to connect
a cable from one output (the Mini has High- and Low outputs) to the External
Audio input, and thereby feed the filter with a portion of its own output
signal. 
This way, a kind of controlled feedback
is created, changing the sound. On our SH-09, this can be done internally:
If nothing is connected to the External Audio input and you activate the
Feedback switch, the output signal is sent directly to the Ext slider in
the mixer section. Set to a moderate leverl, this gives a fatter, richer
sound, but if you pull up the slider you get some very bizarre self-resonating
effects - a growling tone whose pitch depends on the amplitude. If you raise
the Ext slider with the Feedback switch turned off (still with nothing connected
to the External In jack) you will instead get a heavy ground hum - a strange
artifact or defect, that we of course have used (the machine breakdown in
China Boy for example).
3) The CV output no longer delivers CV, but the raw audio output from the oscillator. This modification is intended for controlling the Slumpler, but you can also use this for adding insert effects, before the filter (we have some experimenting to do in this area).
The SH-09 is one of our latter acquirements, and does not appear in our earlier songs. It appears a lot in China Boy as well as in That's a Plenty and Perdido (both under development as of this writing). A terrific device for strange arcade game sounds and solo phantasms in the mad scientist-mold.