Sound barrier under the carpet

[Silverback7739]

I did a search but it didn’t locate anything applicable.
1999 Ranger extended cab
I had to pull the carpet for a deep clean and when I did all of the “stuff” between the carpet and the bare metal came off. The floor of the cab is now down to clean bare metal. What sound proofing/insulation do I need to put down before I relay the fitted carpet? Thanks!!

 

[BobSacamano]

I used this from Home Depot. It's self adhesive and easy to cut.

https://www.homedepot.com/p/Frost-King-E-O-1-ft-X-1-8-in-x-15-ft-Self-Stick-Foam-Foil-Duct-Insulation-FV516/303732248

 

[mhoward]

@BobSacamano: how well does that work? I want to make my truck quieter inside, but some of that sound deadening stuff is stupid expensive (think DynaMat).