Much appreciated, and thank you for the detailed reply. I don't know anything about this stuff, so forgive me for asking this. You said that your second layer as an eva foam with foil on one side - does it matter which side has the foil? Is the foil always opposite the sticky side? Thanks again.
Dynamat has a sticky side, with foil on the opposite side.
I did the same with the eva foam product I used.
So the foam absorbs heat and sound, and foil is the final barrier.
The thing that insulates is the trapped air pockets within the foam.
Same with thinsulste, it's the trapped air within the fabric that insulates.