I would think creative use of acoustic absorbing material would help.
Free-standing pillars of muslin-covered fiberglass bats (even shape
them like bystanding people?) placed near sound sources will help
absorb energy.  Ceiling-hung acoustic absorbents can help control
"booming."

Is the problem the overall volume, or the volumes of particular
frequency bands?

Rod Sprattling

 [ I think it's a tolerance problem: us old folks have different
 [ tolerance for loud music than have the kids operating the carousel.
 [ (And, frankly, I can't tolerate certain music bands myself!  ;-)
 [ -- Robbie