I just measured the revolutions per minute (RPM) of the rotary vacuum
pumps on a Seeburg KT Special, a Seeburg L and a Popper Konzertist.
On-line references for Ampico and Duo-Art rotary pumps recommend that
vacuum pumps for these reproducing pianos are turned at 110 to 125 RPM,
so I was expecting the nickelodeon pumps to rotate in that same range.
However, these nickelodeon pumps are turning much faster:

- The KT Special pump is turning 173 RPM,
- The L pump is turning 164 RPM,
- The Popper pump is turning 231 RPM.

Now I am full of questions.  Are these typical RPMs for these style
pumps?  Are they turning too fast for best operations?  I'm hoping
someone out there in MMD land has measured their nickelodeon vacuum
pumps RPM and can let everyone know what are typical values for
their RPMs.

Thanks,
Wayne Finger