We tailgate a lot during college football season. Before we got our little Yamaha ef2000 (super quiet) we used the onboard Onan Marquis 7000. It provided plenty of power, but since the tailgating activity was going on right around the motor home is was a little loud. On a whim I got an idea to lay a rug under the generator on top of the pavement. It made quite a difference in the sound level. I'm not a sound engineer, but I think the rug absorbed a lot of the sound that would normally radiate off of the hard surfaced pavement. We started doing the same thing camping. The rug we used is heavy rubber backed like the ones a lot of business have changed out regularly by linen companies. A couple of times I added another rug under the mh between the generator and the side where we were partying. I created ripples in the rug and that made even more difference.