Hello Nigel, I am assuming that you have an Aeolian Duo-Art grand
piano. I have a 1922 Geo. Steck myself which I restored many years ago.

You are most likely going to get as many different suggestions on how
to approach this as there are restorers. You say you have good vacuum
and no response to the keys. There are several places to start.

When the roll is playing, do the two accordion expression controls
collapse and open during play? If not, then look for a loose, blocked,
or kinked supply hose.

If they do move, look at the two large expression bellows on the
control box. Do they move up and down during play? If not, you have
no vacuum to the box.

You can also just collapse each of these two large bellows by hand
while a roll is playing. If the notes do not play, it could be you have
no vacuum to the expression box or the internal "knife" valves are not
adjusted correctly. If they do play, then the problem is back at the
accordion stacks or mechanical linkage.

It may also just be a simple problem like the cutout being activated as
this puts the piano action in silent mode, i.e., no vacuum to the stack.

What I have given you may or may not solve the problem as it only looks
at two parts of a very complex system. But it is a start. Do this, or
maybe some other suggestions from others, and let us know what you get.
So many things can go wrong and cause this problem. Good luck.

Kind Regards,
Jim Quashnock
Wichita Falls, Texas
quashnock@aol.com.geentroep [delete ".geentroep" to reply]