I got an adapter from autozone and welded it to my 11hp generator muffler. I used clamps for everything else so when I move it around it doesnt get in the way. I just bought one of those mufflers at autozone and clamp it on. So its not the muffler thats loud now its the mechanical noise. Im thinking of making a box with insulation stapled to the inside and covering it up. I guess I would half to drill a bunch of 1 inch holes in it for cooling. Shit I dont know.