Every so often, someone comes up with a musical instrument that breaks new ground. It needn't be a radical departure in technological terms, but as often as not, it's the implementation of some original ideas on themes already widely developed.

The 360 Systems MIDI Bass is one such instrument.

There's nothing new about sampling, and by the same token, MIDI is a vital aspect of many current electronic instruments. Yet the MIDI Bass takes both these established areas and, with a wonderful leap of imagination, combines them to create a unique machine.

Bass sounds are a fundamental part of almost every genre of music, yet they make fewer demands on the modern technology involved in reproducing them — low frequencies are the easiest and least expensive to sample successfully.

Further cost-cutting comes courtesy of MIDI, which makes a built-in keyboard unnecessary. Pitch can be provided by any other MIDI keyboard, or indeed a MIDI guitar or bass. Velocity information provided through MIDI can then contribute greatly to the instrument's expressiveness, without the increase in price a velocity-sensitive keyboard normally entails. The MIDI Bass can respond to pitchbend and mod wheels, too.

The machine's bass samples are supplied on chips similar to those used for drum voice swapping by Linn and Sequential. Such chips can be quickly changed to provide a library of bass sounds suitable for many different types of music, and each one stores up to four different sounds, depending on the version you buy.

To say that the MIDI Bass is user-friendly is under-statement bordering on stupidity. Simply plug the MIDI Out of your keyboard/guitar/drum machine to the 360's MIDI In, select a sound from 1 to 4, and away you go. Real bass sounds at your fingertips.

But the friendliness doesn't stop there. For instance, 360 Systems have made MIDI channel selection a usable feature for novices by putting a dedicated selector on the MIDI Bass' front panel.

Most of the MIDI Bass sounds fall naturally over the bottom two to three octaves of a five-octave MIDI keyboard, but in case this proves to be awkward, it's possible to set upper and lower limits which govern the range the MIDI Bass will respond to, simply by playing top and bottom notes whilst holding down the Set button.

And as MIDI Bass is monophonic (like most styles of bass playing), the ability to set which priority you want is extremely useful. After all, in some situations it's convenient to have the highest or lowest note depressed as the one that's sounding.

The sounds supplied with the machine are instantly playable in whichever style you see fit, and it's for its universality that a Fender Jazz Bass sample is Sound No 1. It's too conventional to raise eyebrows, but it is good and clear. Slapped Bass does more to draw attention to itself — great for funk, jazz-rock or any music which requires a flamboyant bassline.

'Standup-Pizz' is a finger-plucked double bass that's simply splendid for trio-type jazz and other acoustic music. 'Mini-SEM', on the other hand, uses a Minimoog combined with an old Oberheim module to create a classic synth sound; and thanks to the MIDI Bass, it's velocity-sensitive, too.

Alternative bass guitar samples include a whole bunch of Fender Precision sounds (with or without plectrum, round- or flat-wound strings and so on), classic Rickenbacker and contemporary Steinberger samples, and some esoterica like a Gibson Ripper and an eight-string sample — though there's no Wal yet.

Keyboard sounds include several DX7 patches (including one that's described as 'a truly distressing abuse of FM synthesis') and a Fender Rhodes sample. There's even a timpani chip, which ventures outside the original brief of the MIDI Bass, but works a treat with pitchbend.

Alternative chips cost £35 each, and are changed simply by opening up the box and swapping with the chip already in place. You have to take care not to damage chip legs (ZIF sockets are recommended if you envisage constant sound-changing) and to put the chips in the right way round. A chip inserted the wrong way gets zapped within 10 seconds of the power being turned on, so if you aren't careful, an extremely cheap instrument could get very expensive, very quickly.

I still like the MIDI Bass, though. In fact, I like it so much I don't plan to return the review model. And if that means I have to start reaching for my wallet, then so be it.

Price Two-sound version £299; four-sound version £360.

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