Txslowpoke, I could not tell if you had already bought the "big box generator" and was trying to quiet it down, or, if you are planning on buying one knowing they are noisy and wanting to have a plan before you buy. If you have not bought, the Honda inverter series are incredibly quiet: I have a 3000is which is about 2800w, a very high-quallity machine. Like others mentioned above, with no or little load, the inverter genny's just idle while still putting out 60Hz power, RPM's come up in response to load.
The bad? Cost around $1800 and it is 120v only, no 230v capability.
PS: I did successfully make an 8KW Lister-Petter diesel fairly quiet, but it wasn't easy, and as they say, that's a 'nuther story ;-)
RavensRoost