Super rare SIEL KEYTEK CTS-2000 crosstable synthesizer

Super rare Keytek CTS-2000 crosstable hybrid synthesizer (digital oscillators + CEM 3389 analog filters), serial number 368. The machine has been recently recapped and comes in great working and cosmetic conditions. Full set of cartridges included : 3 ROMs + 1 RAM. Professional packing and UPS Express Saver shipping guarantee.

Background

In the 1980s, the release of the Yamaha DX7 triggered a profound crisis for manufacturers specializing in analog synthesizers, prompting them to actively explore the digital realm beyond Yamaha's patented FM synthesis. As a result, the latter half of the 1980s saw the emergence of a series of digital synthesizers, including the Prophet VS (vector synthesis), Korg Wavestation (wave sequencing), and the Keytek CTS-2000 (Crosswave Synthesis). Despite the Keytek CTS-2000 being a highly innovative synthesizer capable of producing previously unheard sounds, poor marketing due to Siel's dire financial situation, coupled with its esoteric design, consigned this incredible instrument to oblivion.

Usability

Some criticize the design of the CTS-2000, but I see it well suited for the intricate sound engine within the machine. This synthesizer boasts 2 digital oscillators, each implementing 3 slots for selectable waveforms that can be seamlessly crossfaded using a sophisticated 6-stage envelope controlled by 6 sliders. What truly sets the CTS-2000 apart are its envelopes: unlike traditional ADSR with slopes, each envelope parameter influences the length and behavior of the others. While this feature may seem counterintuitive and the resulting interactions complex to grasp, it doesn't mean that incredible results cannot be achieved by simply experimenting with the sliders.

The Sound

The patch editing of the CTS-2000 and its envelope parameters are unconventional, exotic, and intricate, mirroring the unique nature of its resulting sounds. While its presets offer a solid selection of brass, pianos, slap basses, keys, and strings typical of the 80s, what truly sets this synth apart are its morphing sounds. Dark soundscapes, evolving pads with very long crossfading, twisting waveforms and rhythmic athmospheres : even a single oscillator can generate captivating textures that never grow dull. But if you dive further using with two oscillators routed to the CEM 3389 analog filter with dedicated envelope, the results are just astonishing.

Notes

Although the synth has never had any issues, it has been recapped to ensure long-term reliability and has undergone thorough testing before being listed. The package includes 1 original ROM (Rom 3) and 3 cloned cards (Rom 1/2 + RAM). All cartridges work perfectly.