by Grummy » Thu May 16, 2024 2:02 pm
In my experience, there is not much you can do if you are talking about a "contractor" type generator. Sure, if the muffler is original, you probably can play with that to see if you can redirect where it exits and even change the tone of it. Tone alone could make a big difference between annoying and tolerable.
But there is a lot more noise than just the exhaust. What it comes down to is imagine you build that generator in a box. That box still needs adequate intake air for cooling and fuel mixture, but also adequate exhaust porting for the hot air and obviously the exhaust. And, guess where the noise comes out then ? Correct. Right out of all the holes you had to put in the box so it could even run.
You can block noise from heading certain directions however... just imagine your contractor generator running on the ground in front of you. Then imagine it with a 1" sheet of pink foam leaned up against it. The noise will be less in front of that panel, even if the top is not covered. SO, you can attempt some noise control with simple experiments with something like coroplast sheets with an open cell foam glued inside.
And before I forget, MOUNTING.... a lot of noise is amplified if the generator is not mounted on really good rubber mounts. There are quite a few styles of anti-vibration mounts, even small air bags are out there. If your generator is just sitting on a floor somewhere, that alone could double the volume.
Some of the ways RV gensets control noise is by running at 1800 RPM instead of 3600. So that right there drops noise levels. I don't know of any contractor type units that run at 1800rpm.
The newer inverter units already built in a box that run under that 60db level have had an awful lot of engineering put into them to control noise. Not only have they worked hard to manage exhaust note, but equally so, the general air flow that cools both the motor and the alternator portion.
If I was in your shoes, I would definitely try something... we all know how annoying a loud generator can be.