ztheusa

My 2004 Roadster is pretty loud from road/tire noise, and I'm cheap.

I slammed my heavy-duty 4 layer car cover right behind the seats from the rear.

The noise is seriously reduced!

Pounder

I like the Fat Mat from Amazon, cheap ????? cheap = waste of time ????

ztheusa

Waste of time. No! Great sound attenuation.

Fat Mat is expensive, slow, and maybe as good.

LTCHAPPA

You can get a partician in there to help with the road noise and if you take out all that rear interior carpet and then get some dynomate material and cover all the rear surfaces with it your interior sound level will be reduced. Then reinstall all that carpeted stuff.

Z06ster

A long time ago, one of the very first mod's to my C5 was sound insulation. At the time, when I researched it, you supposedly get the best sound dampening result if you insulate the bulkhead (e.g. the slanted area just behind the seats) included in a full body sound deadening. Don't know if the stuff the OP used can get fitment there but something to consider.

knewblewkorvette

I just did my black 99 this Winter/Spring with B-Quiet materials (sound dampening and sound absorbing). It made a significant difference but If I had to do it all over again, I would go with Vettenuts kit as it's cheaper and pre-cut.

https://www.vettenuts.net/index.php?l=product_list&c=66

jackthelad

Cheap, fast, good. Which one do you want? The good stuff is not cheap, and you need to do a lot of hand fitting and sealing the joints to get it done.