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Ryger M2A MIDI to Analog interface board

Ryger Electronics Ltd manufacture an OEM board called the M2A, which is a 8 channel MIDI to +10V analog control board. I've used these boards for a few projects over the years, and as long as their limitations are acceptable in your situation, they are a fine and reliable product. You can also get it as a ready built product complete with dimmers in a 1U rackmount case, the M2LPRO

So what are the limitations? These boards are not too clever. The big thing missing is the ability to do timed fades. What they will do is accept note on and note off MIDI data on any MIDI channel (or omni recieve on all channels) and set the relevant analog output to the level as specified in the note on velocity. Clearly then, doing a fade can be as easy or as complex as your MIDI controller software makes it, and mine has never made it easy. Because of this, I've tended to use this interface for switched or "single level as a time" type applications.

In additioon to note-on/note-off you can also use pitchbend to select which light comes on at 100% (ie bending a note causes the 'on' light to move from channel 1 to channel 2 to channel 3 as the bend gets wider), or program select to select one of a number of preset settings which have the 8 channels off, dim or full on in various combinations.

Although there may well be uses for the pitch bend and program change modes, I can't think of any, and when I've accidently bunged this sort of data at the M2A, it always look junk, usually because I've got a bunch of special effects set up and they don't blend with each other!

You can happily use the M2A with a 'proper' MIDI show controler, or with a sequencer, or MIDI pedalboards. You can theoreticlly use anything that can generate MIDI note-on and note-off messages.

Construction of an Interface

First step is to purchase an M2A. Cheapest place I know of is CPC, who are a lot less expensive than the suggested price Ryger quote, and they in general have stock of everything that is in their (extensive) catalogue.

The M2A needs power, 14-20V, so I tend to use a modular 15V psu, for speed and lazyness reasons. This however is not the lowest cost route to a PSU! A box, some sockets and some time and that is all there is to it.

In the picture above there is a single M2A board. On the back panel is a 12 way terminal strip with 8 channels presented, and a 8 pin standard analog connector presenting 6 channels. Theres a hole drilled for another 8 pin socket, in case I ever put another board in the same box, providing a 16 channel box.

Ryger's Instruction Manuals

Ryger haven't got around to putting up the manuals for the M2A board yet, and somehow I doubt they ever will, so I hope they don't mind me putting a scan of it up here.

• Pages 1,2 - Description and MIDI implementation chart
• Pages 3,4 - System connections and DIP switch info
• Pages 5,6 - Pre-programmed scenes, LED operation and Specifications

Oh yes, be warned - the DIP switches may or may not be the same as the ones as documented on the instruction sheets! Check the markings on the board first