Generators and Sound Proofing
Miguel, I think you bought a 356 about the same time I did. I have a Northern Lights 5KW on my 356 in the port locker. I had custom soundproofing made for it and it is noticable, but not noisy. The main difference in many of these generators and sound is the speed at which they run and the number of cylinders. We run our generator whenever we are away from the dock so we can keep heating/cooling going all the time. It doesn't bother us at all. Before the custom ($1,200) sound enclosure, it was a bit louder, and just enough to be annoying in the cockpit. In the rear bedroom, it was noisy, but not now.
The Northern Lights runs at 1800 rpm with 3 cylinders, whereas the Panda runs at 3600 rpm on 1 cylinder. A friend of mine has a Panda, fully insulated within the Panda soundbox, on his Cabo Rico 38 and it will run you off the boat with noise! I took his boat down the Tenn Tom to Punta Gorda, FL - 1200 miles and we ran the generator very little due to the noise issue.
Marty Colburn, the owner of Lighthouse Landing linked below, has a H41DS as his personal boat, and installed a 6 KW Northern Lights in the port locker with the standard sound enclosure that comes for that generator. I would recommend you e-mail or talk to him about his installation. He is a Hunter Dealer on KY Lake and is first rate. His contact information should be available on the website. If you have trouble contacting him, let me know and I will get the information you might need from him and pass it along.
We have looked at the 41 and it is a great boat!
http://www.lighthouselanding.com/sales.htm