Hi,

I believe that you can use a foam called Poron that is better than what came from Volvo.
I believe it is urethane or a derivative of something close to a neoprene’s characteristics. It touts a longer shelf life for retailers for marketing.

I believe an open cell might capture more noise than a closed cell as why Volvo had it under a regular EDPM mat.
They had thickness concerns and you will have to work with that perimeter as well. The carpet is cut and in a molded shape.

That mat absorbed some moisture and was a good choice thing IMO.
IT was not the greatest in having 30 years of resilience though.
Most materials, of this flexible nature, out-gas or lose oils or plasticizers.
Volvo’s material did well because it was out of the sun and the general atmosphere.

I’m sure there is a tiny bit better foam product available today.
Trick is if can you get the right information out of the rubber folks.
I would stay away from high mass density weight vinyls as they get chilled easily and moisture will collect there.
Their bag is they don’t rot and that’s about it.
The Mass is to deaden panel vibrations just like butyl rubber has done. It has a legacy that is drawing more narrow only.
You want a substrate to have some sound absorption. That adds distance or thickness and cars were not designed for thick blankets to muffle things.

EPDM is a generic term for most rubbers not patented or designed to have some specific quality.
Poron is in that middle line group and is used more and more. It is making foam prices competitive and getting separated out for general use that way.

It doesn’t come with a backing from some of the samples I have seen on the Internet.
I’m sure there may be some made with it or you should add your own.
I prefer to see a breathable membrane on top that is puncture resistant as it supports a thin weaved carpet
in the auto industry.
Expense and weight are the excuses for the bean counters.

There are some things out there from IPD and Summit Racing but are extremely overrated in price for what it takes to make the stuff, IMHO.
DYNAMAT is one that I have seen in one Volvo and it had aluminum foil showing with its name plastered all over it. The car was tricked out by more expense than I care to imagine.
Our youths are living like we use too with less emphasis connected to values being recoupable.

For that reason It didn’t impress me in the least. I should say it was the least material with a questionable worth within marketing claims.
I watch some YouTube that used a DB meter. He was disappointed with the numbers for his efforts plus what was the sound he excepted to eliminate.
A DB meter is not the human mind processing sounds.
What irritates one doesn’t do the same to others.

For the most part, I think going to the trouble to do sound insulating is a waste of time.
If it was any good the engineers wouldn’t have gone to using noise cancellation systems with microphones and speakers placed in specific locations.
You can only isolate the cabin so far from the road and wind noise at ground levels. (:)
An airplane has more of a definitive set of fixed frequencies coming into a cabin.
That can help with selective engineering.

Well I have over thought this thread!
Maybe you can do research to find Poron instead of jute or felt that use to work.
I have used jean denim between the seat foam and the spring frame of both seats in a car.
It helps contain the digging of the springs into the deteriorating urethane foam, of which, helps in overall support and is another topic.

It’s coming down to about how much effort that you want to expend.

I’m here for entertainment in cyber land.
Jeez isn’t that terrible (:-)
I could do worse and go play in a sports game where Nobody remembers the scores years afterwards either.


Phil