The good old Boss DR550. This was my first ever drum machine and as such i can only view it with all the irritation and loathing you can have for a machine that you've spent literally years programming inside out. The DR550 was possibly Boss' first modern drum machine of the 'hundreds of sounds in a black box' variety. This and the Alesis SR16 marked the death of real drum machines for many years although looking back on it now its not such a bad little box.

Actual specifications for the DR550 seem a bit rare on the net but as far as i can tell its got about 50 or so 16 bit sounds, two outputs and midi input. I think theres space for two banks of 88 patterns but ther may well be four banks available.

The mods we've added to this machine are pretty plain to see as they consist of an external patchbay mounted on the side of the machine. The patchbay consists of:

21 way main patchbay: Connections can be made between any of these sockets using standard minijack patch cables. Each connection will cause some or all of the sounds to distort and warp in all kinds of unlikely ways. If you are using the internal pattern sequencer on this machine, some patchbay connections cause the tempo to speed up and slow down in bizarre ways along with random pattern swaps and splices. Audio-wise the patchbay on this machine is savage. A lot of the patchbay connections produce some of the most brutal drum grinding and distortions we've ever heard, and as you can imagine thats up against some pretty stiff competition! Several connections create bursts of evolving noise that slowly fade away into random noise and pulsating percussion. This machine is a speaker eater so proceed with caution ;-)

2 x patchable momentary buttons: As mentioned, some connections create bursts of slowly fading noises but if you leave these sockets connected everything gets violently out of hand very quickly. These two push buttons can be patched in line with any main patchbay connection so you can tap a button to make the connection and create a burst of noise, or you can use them to create bizarre drum fills.

2 x patchable switches / 3 way multiples: With the switch turned on these three sockets are all connected together internally. This acts like a multiple on a modular synth in that any cable taken from a main patchbay socket and plugged into a multiple socket will have its signal present at the other two sockets. Cables can them be taken from these sockets to elsewhere. Basically this allows you to connect three main patchbay sockets together at once. The switch turns the connection on and off between two sockets and the remaining socket for more intricate switching and patching arrangements.

To hear demos of what this machine can do just click on any of the players below. Unbelivably there are only two different internal patterns on each demo. The variations are created just by patching and repatching cables in the patchbay.