I'm working on a 1978 "Modern" Aeolian with plastic valve blocks.
No component exhibits leakage when tested on my work bench, but the
piano plays very weakly, even though the reservoir is completely
collapsed.  The bass end plays louder than the treble.  Has anyone
faced a similar problem?  Are any Standard replacement stacks
available?

Carl Kehret
pegkehre@tx3.net.geentroep [delete ".geentroep" to reply]