Hi Joe,

> Speaking of connectors in the back, if I were to install a DIN

socket

> in back of an A100 frame and wire the midi signal internally to the
> A190 and A191, would simple wire work OK Shielded two-conductor

Thin

> coax

The simple introductory book I have on MIDI says that screened twin
core cable of audio quality is fine. BUT, MIDI is not
straightforward. It works off a 'current loop', with opto-isolators
used to ensure that interconnected bits of kit are electrically
isolated from one another. The book strongly advises against trying
to drive two inputs from a single output (you wouldn't be able to
guarantee that either input would work properly) - this means that
you would still have to run your A-191 from the 'thru' of the A-190
(although conceivably you could connect them internally). Also the
point of using screened cable is to prevent interference
from 'escaping' from the lead, and not from noise penetrating it -
the screen on a lead is attached to both pin 2's at either end, but
the pin 2 on any socket is *not* connected to the chassis, in order
to maintain the isolation of all bits of kit.

I'm not sure how helpful the above is - you were obviously expecting
to connect things internally, only it might be less simple than you
had imagined ( ).

Tim