Hi Mike, yes noise is an issue and very hard to do anything about with an air cooled unit that can`t be fully enclosed. The last one I did was a Kubota Lowboy generator, I built it a rectangular concrete enclosure with louvred doors on all four sides. I had to fit stainless steel fly mesh to the inside of each door to keep out vermin and the wretched mud wasps. It worked very well and was remarkably quiet, I`m thinking to do something very similar for this, probably with an in the ground exhaust system. It will go behind the new shed in between the two 5000 gallon water tanks, which should help muffle the sound.
I`m going to hook up one of the 240 volt outlets to the house as a back up for blackouts and the 3 phase to the shed so I can run industrial machinery. Now all I need to do is buy me a milling machine. Not many available in Tasmania: One in Hobart with a stuffed drive motor ($900 for a rewind) and another going for auction next week. I think I might put in a bid at the auction.
The good news is my electrician friend will be back in Tasmania next week so we can start wiring the new shed.
Bob