[SEL] reducing noise on portable generator

[ivan]

 Ok , this is for use at Portland so its on topic.  But I dont want to p***
everyone off listening to a gen howling away .. So I put together a belt
driven generator so we can run the ac in the camper by day  . Its chuggin
along at 2400 rpm , with 115 under a 2400 watt load . Much better than one
screaming at 3600 rpm .  But how to quiet it down a little more  ?
 I would like to put a smaller pulley on the gen itself so that I can lower
the speed a little more ,target is1800 rpm and I have one of the lo tone
mufflers from briggs  .So its a little quieter than a jet turbine .
Suggestions ? Ivan