images via
this auction via
Rob
"The Chroma was the last synth made by synth giants Arp Electronics, it was rebadged by the Rhodes company when they bought Arp out in the mid 80's. Rare synth, approximately 2000 Chroma keyboard's were made, but only around 200 Chroma Expanders were produced. The Expander has all the same superb sound as the Chroma keyboard, but fortunately none of the bulk. The Chroma keyboard is HUGE and weighs about the same as a CS80! [
Update via Joseph in the comments: "Hi There the CS-80 Weighs 220 1/2 pounds (100.3 kg) And the Chroma weighs 71 pounds."] The Expander by contrast is very portable and takes up very little space which is great.
Here is a brief technical specification:
Velocity and aftertouch sensitive. 16 Oscillators. (Can be either 16 note polyphonic with one oscillator per voice, or 8 note, with two per voice) Pulse and Sawtooth waveforms. The PULSE and SAWTOOTH both have width controls, so the Sawtooth can be swept from a Sine wave through Triangle to Sawtooth. Multimode filter, 2 pole Band pass, 2 pole Notch, 2 pole High pass, 2 and 4 pole Low pass filter modes. White and Pink noise. 4 EGs. 2 LFOS with 16! different waveforms. Each VCO has independant portamento. Sync. Ring modulator. FM. Unison. It has a very flexible architecture much like a modular synth- but with patch memories.
Fab sounding synthesizer, great for string, pad sounds, resonant sweeps, vocal sounds, basslines, leadlines, FX. It can sound very percussive too, capable of cutting right through a mix. It has a recognisable classic 80's powerful analogue sound and was used on tons of records, Herbie handcock in particular is a heavy user, the lead line on Rockit was the Chroma.
To hear the sound of the Chroma in action i highly recommend checking out this Youtube video [see
this post]: (Herbie plays the Chroma, 2:43 minutes into the video)
As well as restoring the electronics and case, i also added the new midi kit from the guys on Rhodes Chroma website, check out the midi kit specification
here.
I recommend checking out the
Rhodes Chroma website its an excellent resource!"
images via this auction
Rod wrote in to let me know of Combo Nation, a new combo organ forum. Check it out. 
"This is an updated version of the low frequency oscillator on the classic analogue synthesiser, the Korg MS-20. It features two output waveforms, triangle and square. But, the design also incoroporates a 'Shape' control that affects the rise and fall times of the triangle waveform, and mark-space ratio of the pulse waveform. Therefore, you can get sawtooth and reverse sawtooth from the triangle output by using the Shape control.
images via this auction via Rob
image via s o n i c b r a t who has this, a Marion MSR-2 and Oberheim Matrix-1000 for sale on the forum.
