[sdiy] passive MIDI merge?

[Neil Johnson]

All,

> someone on the list already built a midi patch bay (Neil Johnson, please
> standup)

*waves*

> Im not sure how far the project has gone as far as PCBs, etc go...

Sorry for not responding earlier, been getting some very late nights
recently, sleep slowly catching up in me.........

> > 5) Build/buy a MIDI patchbay.

It does sound like a job my MIDI Matrix 2 could cope with.  There are
more details on my website:

	http://www.njohnson.co.uk

in the hardware projects section.  I confess, this site is in need of a
major revamp, so I apologise if its not as up-to-date as it could be.
But I digress.

The MM2 was published in "Electronics and Beyond" earlier this year, so I
suggest if you want the full details that you contact them for back
issues.  Links provided to the magazine site.

What does it do?  8 MIDI ins, 8 MIDI outs, 64 patch locations, instant
recall from front panel or MIDI patch change message (what else?), very
simple to use (I think, but that opinion is biased!) and only 1U high.

I recently had a PCB panel made up by PCB-Pool in Ireland for someone.
The single panel with all three boards (main, front panel, transformer)
came to around 90 UK pounds.  Perhaps a tad expensive, but that's the
one-off prototype pricing for a double-sided through-hole-plated PCB -- if
I had 50 boards made the cost would be more like 22 pounds each, but I
don't have 1,100 pounds to spare.

If anyone wants more details I'd be happy to go into it further, maybe
off-list though, so email me.

I'm currently working on a range of smallish mini synth modules, along the
stickle-brick approach.  Each one does one thing (VCO, VCA, VCF, wave
shaper, etc) with a design limit being a PCB sized 2" x 2".  This
constraint limits what each does, but also means they'd be rather good if
you want to build a polyphonic synth, for example.  My plan for these
modules is to start with a mono modular, for prototyping, testing out
architectures, and then to progress onto a polysynth.  Oh, and all the
signals are on a 0.1" two-row header, with the aim of them being mountable
on a back-plane.  I'm still planning on keeping the supply connector
separate though, compatible with Oakley and MOTM.

Anyway, one day I'll get a PCB made up of some of my designs and try them
out.  I'll let you all know when I get some results.

Take care y'all
Neil

--
Neil Johnson :: Computer Laboratory :: University of Cambridge ::
  http://www.cl.cam.ac.uk/~nej22           +44 (0) 1223 763 646
----  IEE Cambridge Branch: http://www.iee-cambridge.org.uk  ----