Can anyone tell me how much vacuum a Wurlitzer 146 or 153 should pull? My
North Tonawanda 188 (roughly the equivalent) runs about 28 inches of water
with all tracker slots closed. When playing it runs 20-25. I added a set of
bells operated by vacuum, and they drop the vacuum enough so that some of the
organ notes drop out. I thought there was plenty of reserve in the vacuum
supply, but that apparently is not the case -- unless the vacuum supply is
weak. An electric suction box is temporarily fixing the problem.

Fritz Gellerman