Hi Bob,  We have a Concertola roll changer at Ashorne Hall; it was
acquired some years ago to compliment our Aeolian Pipe Organ.  It was
not original with our pipe organ but purchased separately.

I have restored the device and, indeed, we had it gold plated as well,
but in the course of the restoration I dropped a clanger.  I failed to
spot the two in-line bleeds cunningly hidden in two of the tubes on the
rear of the control valve boxes.  Opps!

Are there any tubing diagrams for the Concertola, or can you advise me
where they should go?

Thanking you in advance

Paul Camps