With all the current talk about MIDI, it is easy to forget that some companies have been developing their own interfacing for some years. Of course, the Roland system has received a lot of exposure with the DCB (Digital Communication Buss) allowing the MC range of sequencers to be connected to their polysynths, and also the DIN connectors which sync the TR drum machines and bass-line.

However, there is another system which has been quietly developing and expanding over the years, one which has received less publicity because of the limited numbers of dealers importing it. But now that several new people are bringing over the Oberheim system from the States, let us hope that this system attracts the interest it deserves.

The heart of this system is the DSX sequencer which can control the whole family of Oberheim polyphonics - the OB-X, the OB-Xa and the latest model, the OB-8 via a computer interface. It also has 8 separate CV and gate outputs to control up to 8 analogue synths of the 1 volt per octave variety. It has a capacity of 6,000 notes and is capable of 16-voice polyphony. It can store up to 10 sequences at any one time and there is cassette storage for building up a repertoire of sequences. Each individual sequence can be independently recorded over 10 tracks and there are two recording modes: Real Time (with a 1/192 note resolution) or Quantize which will auto-correct your playing to ½ note (minimum) maximum or 1/32 note (demi-semiquaver) minimum. There is also a programmable metronome with an internal speaker.

The Merge feature gives the DSX a particularly useful flexibility. It allows sequence looping with the ability to listen to different tracks each time round, chaining different sequences and inserting transpositions and sound program changes. This gives virtually unlimited variation within the total memory capacity of the sequencer.

The DSX is also designed to work side by side with the DMX or the more recent DX digitally-sampled drum machines (see DX review in E&MM Sept '83). The DMX works on replaceable voice cards while the DX's sounds can be changed using new EPROMs. Both machines can store 100 drum patterns (up to 99 bars) each and combine these into fifty songs. Of course the syncing facilities on both the drum machines and the sequencer allow them to be used with compatible equipment from other manufacturers.

Full marks to Oberheim, who have been producing this totally internally compatible system since 1979. Each new piece of the equipment has upgraded the potential of the system (the OB-8 improving on the spec, of the OB-Xa for example) or made similar facilities available at a lower price (the DX coming in at just over half the price of the DMX with most of the features) but ensuring that the original does not become obsolete.

Thanks to the London Rock Shop for letting us play around with their 'system'. Current prices are DSX £1,395; DMX £1,995; DX £995; and OB-8 £2,995. An extract from 'the Sound of the System' - an Oberheim demonstration single - will be included on the first of the new series of E&MM demo cassettes available in the New Year.