Many of his designs and explorations of classic synth and effect architecture found their way into top musicians' possession and have stayed there - I've delivered several to their studios,and they are still there decades later.

The CS50 is great in its own right as one of the warmest, most organic synths ever made, with a wonderful keyboard action and user interface. But this one is unique: Juergen's custom modification turns it into a modular controller as well.

The custom 19-inch rack connects to the CS50 with a set of DIN leads, and acts as a wonderful controller for a modular - or any suitably equipped monosynth. Although the polyphonic features he planned hadn't been completed, it still turns this instrument into something even more powerful and unique. A copy of Juergen's invaluable paperwork is included.

Cosmetically, the CS50 is a bit tatty at the back and is missing the cover for the mains lead on the underside, but is otherwise generally good. The important bits - keys, controls, front panel - are very good.

The rack is excellent, with (we presume) Schaeffer etching. Self powered (230V). Open frame construction behind the front panel, so it must be safely installed in a professional rack.

Two V/Oct outputs with high/low note priority, tune and transpose functions. It also brings out CVs for Aftertouch, PWM oscillator and Sub Oscillator. The 5-pin DIN jacks are *polyphonic* V/Hz outputs - they were intended for a polyphonic modular system, which was never realised. What you use are the 1/4 inch V/Oct outputs.