MIDI over long cable runs

[Arturo Mieussens]

Michael Bacich wrote:

[snip]
> The MIDI signals will be originating from the keyboard of a modern
MIDI'd pipe
> organ, mainly just to let the organist play the occasional piano or
bell/chime
> sound from a MIDI module, so the cable and interface won't have to
deal with
> any high-bandwidth data such as sysex or multi-channel sequencer
data.

This might sound stupid, but...  Why don´t you place the module
closer to the organ and run long balanced audio lines instead of long
midi lines?

I only think you would need long midi cables if the module has to be
played by other controler located far away, and then you could buy a
small synth module for the organ (kurzweil micropiano, alesis
nanopiano and nanosyhtn come to mind), that of course would be more
expensive, but if you have a church or theater that big, money should
be no problem. But then again, why would you be asking to make it
yourself?

Hmmm.. And what if your module doesn´t have balanced output?. Maybe
you don't need it, line level signals can travel far away without
much distortion, or you can get a couple of unbalanced/balanced and a
couple of balanced/unbalanced audio transformers

Anyway, I would use a regular midi in circuit, followed by
amplification (balanced, a couple of op-amps should work), maybe a
differential amplifier (or atenuator, probably) and then a regular
midi out circuit. This seems to be a very simple and usefull project,
maybe i'm wrong about getting another module.

And what if we modify the midi signal comming from the controler and
make it balanced?... this sounds interesting, balanced midi. and of
course we should modify the signal before the module's midi in.
(could a couple of transformers work here?)

Good luck.
Arturo Mieussens.