Does hood liner reduce interior noise?

[AcampoDave]

Thanks, Tinnitus sucks but I'm getting used to it now.
At the spur of the moment today I tried something kinda funny. I knocked another easy decibel off by shoving foam pipe insulation between the bed and cab right at the bed floor level. It seemed logical that keeping the noise confined under the truck would help and I already had the pipe wrap so...why not.