Digitana develop custom interfaces for vintage EMS Synthi synthesizers. They recently collaborated with Future Sound of London on the Synthi AKS KS Expander, an expansion unit for the EMS Synthi AKS Keyboard Sequencer (KS). The expander added a pair of oscillators, Sample and hold, Slew limiting and an LFO. When developing the KS Expander they saw how easily it could become something more in its own right. And now it has evolved into the SX-1 Stand Alone Expander.
They’d already done all the work with the KS Expander and so pushing it further, and the case wider, I imagine became an obvious next step. The SX-1 has all the same features as the Expander and can indeed still be used as one for the Synthi, but the SX-1 can very much stand alone.
In addition to the dual VCO’s, Sample-and-hold circuit, Slew Limiter and LFO the SX-1 expands into dual envelope generation, dual filters and slope generation. There are also two effects circuits of analogue delay and distortion.
The VCO’s feature sine, triangle and square waves with voltage controlled wave folding for giving the sound some high harmonic aggression. Pitch control is available via CV inputs or the integrated MIDI-CV converter. Wave-folding can be modulated via the LFO with triangle or square shapes. This can also be applied to the oscillator pitch.
The surface is festooned with toggle switches for engaging or bypassing routing and modulation. There’s a small amount of CV patching which is mainly concerned with the VCOs. The delay and distortion effects add a lot of interest I think although these can also be bypassed.
It’s an achingly beautiful looking box. Very much in the EMS style. It looks warm and inviting and the allure of the coloured knobs is quite enticing.
There’s currently no pricing or released date on the SX-1 and so some of the features may change with the final release. The Synthi ASK KS Expander was always built to order and try as I might I can’t find any pricing information on what that might have been. Synthi AKS Keyboard Sequencers tend to go for around £7,000-£10,000 second hand so I get the feeling this isn’t going to be cheap and cheerful.
More information on the Digitana website.