DACS MIDI Patchbay
Ian Gilby investigates this novel solution to your MIDI wiring headaches.
If there's one thing that's guaranteed to dry up the creative juices, it's having to grope around behind keyboards, sequencers or effects units in the middle of a recording just to unplug a MIDI cable. It can easily knock your inspiration for six and completely ruin the session. The way to avoid this aggravation, of course, is to invest in some form of MIDI patching or routing system to connect all your MIDI gear to one central device, thereby permitting any re-routing to be expedited quickly and with the minimum of fuss.
But don't such systems cost an arm and a leg? Well some do, some don't; it depends on the sophistication of the unit. As always, you get what you pay for, so if you want multi-way switching and the ability to store and recall configurations from memory, then you will have to part with serious money. But don't worry, there are alternatives for those on a tight budget, which can provide an equally good antidote to everyday MIDI interconnection headaches. One such device is the aptly-named MIDI Patchbay from a new British company called Digital Audio & Computer Systems Ltd (DACS).
This 1U high, 19" rack unit allows up to 10 different MIDI instruments to be interconnected. Instead of using switches to route MIDI data from one source to a range of possible destinations, instruments are 'patched' together directly using ¼" jack-to-jack patch cords, as on a conventional audio patchbay. Except that it is not audio signals that are being interconnected, it is MIDI information. Full marks for novelty value, at least. Actually, there is method in this apparent madness: it adds considerably to the flexibility of the unit, and that's an important consideration on any routing system.
The unit is very well built. The steel front panel is divided into 10 sections, each housing four plastic mono jack sockets arranged in two rows. These are fixed with washers to a sturdy metal plate behind the grey front panel, and the plate itself is screwed to the front panel. All sockets are soldered top and bottom to two epoxy printed circuit boards, which are spaced about an inch apart with risers. This gives the whole construction a welcome air of rigidity, which should hopefully translate into a prolonged working life for the DACS unit. Patchbays can come in for a lot of stick in the studio, so they need to be able to withstand regular and continuous plugging and unplugging without falling apart. The DACS patchbay looks like it should cope admirably.
The unit is easy to install into any MIDI setup: 10 pairs of standard 5-pin DIN sockets are provided on the rear and you simply connect these to the appropriate MIDI In and Out sockets on your instruments. On the front, the four jack sockets in each section provide access to one MIDI In, two identical processed MIDI Outs, and one unprocessed Thru connection (being a duplicate of the input signal connected to the rear MIDI In socket). Taking a patch cord from any front panel Out socket allows you to connect that particular instrument to any other simply by plugging the other end of the cord into the required In socket. With the patchbay mounted in a rack, connection changes can thus be made easily. You don't have to worry about programming or accidentally erasing a memory either, you just get on and use it. If you want to change a connection, it's a second's job.
In use, it quickly becomes apparent that the DACS patchbay has been well thought out. The provision of two parallel front panel Outs per instrument and one Thru means you can dispense with MIDI Thru boxes entirely. If you need more than two Outs, you can simply patch the Thru signal from the first section to the In of a second section and utilise the two additional Outs for more connections. 'Daisy chaining' several sections in this manner does not produce any appreciable delays in MIDI data transmission, thanks to the active circuitry employed.
Where relatively permanent MIDI connections are to be made between certain instruments (eg. master keyboard Out to sequencer In), there is no need to have a patch cord plugged directly between the source and destination. Instead, the required two sockets can be interconnected - or 'normalised' as it is called - simply by soldering a piece of wire onto the solder pads on the appropriate circuit board of the DACS unit. These are clearly labelled for all four connections: In, Thru and both Outs. Normalising is common practice on most good patchbays, and makes for a neater more flexible routing system. If you change your mind at any time, inserting a jack plug into the left-hand Out socket will temporarily 'break' the normalised connection, allowing you to route that particular output somewhere else. Removing the jack plug restores the normalised configuration.
If you were wondering where the DACS patchbay gets its mains power from, the answer is that it doesn't need any; it draws the required current from the MIDI connections themselves, so it is important to ensure that both MIDI In and Out on each instrument are always connected. If long cable runs are anticipated, an external 5-volt DC power supply can be plugged into the back panel input socket for extra power. For most installations, however, this will not be necessary.
From a safety viewpoint, each MIDI In has its own plug-in earth link. DACS advise that these not be removed unless doing so is the only way available to overcome a persistent earthing problem from a rogue instrument. It's good to see them included.
I was very impressed with the DACS unit: it is robust, highly functional, and its thoughtful design allows a great deal of flexibility in routing. My only reservations are the lack of provision on the front panel for identifying what instruments are connected (though you just about have room between the jack sockets to scribble a name with a chinagraph pencil), and the 10 sections could possibly do with being numbered in some way on the front panel for better differentiation.
All in all, the DACS MIDI patchbay is a good unit that will pay for itself a thousand times over by alleviating unnecessary interconnection hassle from any MIDI setup and allowing you to get on with the more important business of making music.
£117.87 inc VAT/p&p.
DACS Ltd, (Contact Details).
Review by Ian Gilby
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