Hardly Whisper quiet!
Joe,
Here are some suggestions for you to try.
On the inside of the door, I used something like dynamat rubber padding about an inch thick and custom cut it to fit around the detergent and rinse aid dispensers leaving enough room for the wiring not to be pinches and away from the bi metals.
I have also used 3 inch UNFACED fiberglass and again kept it away from the dispensers.You can actually cover the rinse dispenser with the fg but it has to be thinner.
Since I have a ceramic floor under my machine like you do, I used the 1" thick dynamat stuff on the floor to absorb the sound as well. Fiberglass won't work well and will catch all sorts of dust and stuff.
I covered the lower panel with a piece of rigid fiberglass board cut from A/C ducting and glued it to the lower panel and kickplate, trimming out wherever needed to clear components on the cross member.
If you can, bring the insulation down to the bottom of the machine on the sides and back to the floor leaving an opening for the blower to get an adequate supply of air. Maybe cut it away totally in that right rear corner, Again, thinner rigid board will work better than the looser batt type.
One thing I have tried in the past that worked when the machine was not yet installed was to remove whatever insulation there was and to spray the whole tank with a coating or two or three of Bedliner or undercoating spray. Top, sides, back and bottom. Also inside on the surface of the door. This will cut down on the "ringing" sound that can be heard when the water hits the porcelain tank. Stainless steel has a duller sound when hit with the water.
Of course, I ran it thru a few drying cycles to cure it and get rid of the smell and did it in the garage with the door open so the smell would be gone before installing it.
Then I insulated the tank to conserve the heat and quiet it down further.
I had a Monterey built by WP that had that thick black mastic all over the tank including the bottom and that machine was remarkably quieter than anything Hobart made. I still put the deadening in the door and under the machine. Made a real difference in the noise level in the house.
Ironically, I have a 22 and 23 built by WP and they cheaped out on the mastic as it covers only the top and half way down the sides and back. But for some reason the 23 Imperial is still pretty quiet by KA standards.
You may want to check out Dynamat's website and see if they have something in a roll that you can use too to replace or augment the fiberlas you have on the machine now or in addition to it too.
Hope this helps a bit
