I have recently acquired a Welte Licensee Vorsetzer that needs a little
finishing up.  It was run with a remote centrifugal vacuum pump which
is quite loud.  I have a bunch of noise deadening foam and a plan to
make a baffled housing to quiet the pump, hopefully enough that it can
be installed in the machine directly.

I know that some late model Weltes has a centrifugal pump (turbine) and
that it was supposed to be quiet.  I would like to get any information
on that system that is available to save time in developing my turbine.
Any information including general and specific information as well as
pictures or engineering drawings and materials used in construction
would all be very helpful.  Also, any other experiences of others
attempting to quiet a multi-stage centrifugal vacuum pump would be
helpful.

The unit I have has a separate fan cooling the motor so the pump and
the motor need to be quieted separately.  My basic plan is to provide
multiple baffles to the air flow, especially the exhaust and to provide
a rubber suspension for the motor to prevent transmitted vibration.

Spencer Chase
http://www.SpencersErolls.com/

 [ The cast aluminum turbine pump and motor assembly made by Motora
 [ (Chicago) for installation in Welte and Recordo player pianos is
 [ suspended inside its box using four limber springs, and the box
 [ is lined with sound-absorbing felt.  The unit is quieter than
 [ other turbine pumps, nonetheless Mr. Stoddard and Dr. Hickman
 [ judged it too noisy for installation in the Ampico B grand piano,
 [ so they retained the more expensive low-speed box pump.  A pump
 [ mounted inside a Vorsetzer must be virtually inaudible.  -- Robbie