>So, I think Paul's concept of a switching jack is still best...
Absolutely, no need for the switch.
>... but I think the "switch jack" should be the second output not the
first.
But I don't get this. Surely the top output should be the sum of the top
row of inputs. Inserting a jack in these automatically disconnects this
from the next three. Its also easier to do, since you can do this with
the NC contacts in the 112A.
Its what I would do :-)
Regards,
Tony Allgood Penrith, Cumbria, England
Oakley Modular Synth and TB3030:
www.techrepairs.freeserve.co.uk/projects.htm
My music: www.mp3.com/taklamakan