2021 Accord Touring 2.0T
With the rear area creating the most noise what do you guys think of this idea.Your correct the front doors did little.in terms of road noise. Actually the biggest difference came from the trunk area and rear quarter panel areas or the rear wheel wells, which are hollow with these tiny little pillows shoved in for sound absorbtion but are basically worthless. The trunk area def made the biggest difference(if you have a non hybrid probably under the rear seat as well). Everywhere else you mentioned has pretty thick carpeting for the most part to absorb the sound except the doors of course, even the front firewall area. I'm not sure about the headliner but I'm not sure I really want to deal with that as it as well is pretty heavily carpeted up there. I'll be adding a roof rack/cargo box soon for traveling and if I hear extra noise when it's installed ( plan on taking it off when not in use) I may consider it. But having the hybrid and it being so quiet I can hear where noises are coming from very easily, and trunk wheel well areas by far made biggest difference in terms of significantly reducing interior road noise. Really only reason I'm doing the rear doors because I have found the door handle mechanisms like to come loose and rattle on all the doors so I'm going to take the rear door skins off anyways to fix them so might as well. I also only really did the front doors because I upgraded the speakers. But 100% trunk area including the spare tire area def the way to go.
On my generator for the Florida storms I have a horse stall Matt it kills all the vibration and a lot of the noise from it. Purchased at Tractor supply . Here is the link 3/4 inch thick maybe add some of this to the trunk area