You may recall some postings and replies from last fall about my
problems with getting the pipes and piano tuned together.  There were
several replies which helped define the process, as we had [already]
tuned the piano to A=440 Hz.

Then we tuned the piano to A=435, but the pipes were still flat when
tuned as sharp as they would go.  I asked about air pressure, but got
no answers beyond the fact that it takes about 5 inches of water to
make the pipes sound.

I made a port to monitor pressure at the inlet to the pipe stack.  The
short answer is that it takes between 7 and 8 inches of water pressure
at the stack inlet to bring the pipes in tune with a piano at A=435
with the pipes as sharp as they will go.  To get the pipes adjustment
in their mid-range it takes the piano tuned to about A=420, so I am
guessing that at least these pipes were made to about an A=420 standard.

Thanks to everyone for the comments and help.

Scotty Greene - DeBence Museum