ONE AREA WHICH requires some thought when your collection of MIDI machines starts to grow is just how you're going to connect them all up. The simplest way, of course, is to chain them together. But aside from the fact that not all instruments have the requisite MIDI Thru socket, chaining is generally frowned upon due to the risk of data corruption when more than two or three instruments are linked up in this way.

The next step is a MIDI Thru box. This can be passive (merely passing the data out of several Thru sockets) or active (allowing you to switch individual Thru sockets in and out). But this is a relatively simple setup which won't necessarily provide all the flexibility you require.

Cue the MIDI patchbay, which allows you to connect several MIDI inputs to any of several MIDI outputs. Latest in a long line of MIDI patchbays which has included offerings from Quark, Sycologic, Akai, 360 Systems and Yamaha is the 5X5 MIDI Switch from British company Philip Rees. At under £100, the 5X5 also happens to be one of the cheapest MIDI patchbays, the only comparably priced unit being Akai's four-in, eight-out ME30P.

As its name suggests, the 5X5 allows five MIDI inputs to be connected to any of five MIDI outputs. The only proviso is that no more than one input can be routed to an output - this would involve two MIDI signals being merged together, which would require a level of sophistication greater than that necessitated by the mere rerouting of signals.

It's also possible to chain together up to three 5X5s, or a combination of 5X5s and X5X Switch Expanders, to give five-in/ten-out or five-in/fifteen-out setups.

Unlike the other manufacturers noted above (with the exception of Quark), the 5X5 is a hardware-only device, ie. there is no microprocessor control. There are no opto-isolators in the MIDI circuitry, allowing the unit to achieve a fast throughput. The MIDI inputs are floating relative to each other, and isolation is provided by a custom-designed transformer.

By necessity, though, the above approach means that the 5X5 is devoid of programmability, and thus of the memories to be found on other units such as the ME30P and 360 Systems' MIDI Patcher, which allow you to store your routings and call them up either from the front panel or over MIDI. On the other hand, the individual input selector knobs for each of the five outputs make changes to routings an easy process. These, together with the spaces provided on the front panel for labelling your five MIDI inputs and outputs, mean that you can see at a glance what is assigned to what.

Rees have also provided each input selector with a "zero" setting which switches off the output to the relevant MIDI device. This can be a handy way of temporarily "removing" a particular instrument from a sound texture, but as with all changes to routings on the 5X5, you need to take care to avoid the possibility of the MIDI drone.

This is because, as a hardware device, the 5X5 takes no action to remedy what is essentially a software problem. It's worth bearing in mind that if you're using instruments which send and receive MIDI active sensing then there's no problem, because the receiving instrument(s) will take care of business as soon as the MIDI data flow is interrupted. On the other hand, it can be preferable to avoid the use of active sensing - notably if you're using a sequencer, where such "additional" data can use up valuable memory.

One area where a MIDI patchbay really scores is that of storing patch data via System Exclusive codes to a central machine such as a computer running patch librarian and/or editing software - something which is becoming increasingly common. In this context, all your instruments need to be able to both send and receive over MIDI - so having an equal number of inputs and outputs makes a lot of sense. The 5X5 allows you to connect four instruments in this fashion (the fifth input/output being for the computer or dedicated MIDI storage device).

The 5X5 performs its allotted task well, if without the finesse of software-controlled MIDI patchbays. Its clear front-panel layout and ease of operation are a definite bonus, as are its expandability and its reasonable price.

Still, you should think carefully about whether you'd miss programmability and the possibility of MIDI control, whether the lack of evasive action over MIDI drones will be a problem, and whether other, more expensive units (notably the Quark MIDILink 999) will provide you with more flexibility in the long run.

Price 5X5 MIDI Switch £85.95, X5X Expander £69.95; both including VAT and p&p

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