Is acoutsic foam inside door with sound damping sheets worthless?

[Marquisboys]

Would it be pointless to put acoustic foam over sound damping sheets on the outer door panel? Like the egg carton foam or even 1" foam like this http://www.parts-express.com/sonic-barrier-1-acoustic-sound-damping-foam-with-psa-18-x-24--260-525

[Kevin M]

I have the same foam in my doors. I'ts been there about two years. The adhesive backing is pretty lousy. I used some super 77 after it came off. Its held ever since. Improved the midbass response pretty dramatically.

[Marquisboys]

Ahh ok yeah i think thats what ill do than. i already have the doors sealed with Q-mat and i seen in a video someone used F.A.S.T ring foam around there speaker and said in improved the sound quality so i figured why the hell not do the whole door in foam lol. Did u cover the whole inside of the door with that foam or just a little section behind the speaker?

[CarAudioFab]

Ahh ok yeah i think thats what ill do than. i already have the doors sealed with Q-mat and i seen in a video someone used F.A.S.T ring foam around there speaker and said in improved the sound quality so i figured why the hell not do the whole door in foam lol. Did u cover the whole inside of the door with that foam or just a little section behind the speaker?

The biggest help with the FAST rings is the fact that it directs the sound through the cut location in the door panel. It doesnt allow sound to bounce around inside the panel itself which can lead to cancellation and vibration of items (wiring harness etc) within the door panel.

Here is the video he mentioned:

[Marquisboys]

Yes exactly, that build was really clean btw. I was thinking of installing those rings and covering the whole inside of the door with foam also

[Kevin M]

Ahh ok yeah i think thats what ill do than. i already have the doors sealed with Q-mat and i seen in a video someone used F.A.S.T ring foam around there speaker and said in improved the sound quality so i figured why the hell not do the whole door in foam lol. Did u cover the whole inside of the door with that foam or just a little section behind the speaker?

I covered the hole inner door skin with it

[mrd6]

Keep in mind that stuff you linked is open felled foam, if it gets wet it will absorb water and has the potential to mildew or mold, I would look for closed cell foam if you're putting it in your doors

[Marquisboys]

Ahh good call lol i dont need to be smelling mildew and mold

[trumpet1]

A better solution is to use fiberglass insulation. Foam that can absorb water can also absorb sound, which counts out closed cell foam for treating the inside of a door. Closed cell foam rejects sound similar to how it rejects moisture. Open cell foam has already been said in this thread to be a bad choice. Fiberglass insulation is cheap, readily available, and with a single layer of plastic it will be protected from water yet sound can still be absorbed.

Write-up with photos: http://www.513electronics.com/easy-way-electronics-blog/make-your-speakers-sound-better-with-insulation-sound-damping-part-9/

[Marquisboys]

oh wow didnt even think of fiberglass insulation. I going to be using that i can get a lot for dirt cheap. I seen that he put it on the frame closet to the door panel, ill probably end up doing that and on the inside of the door. Think ud be able to hear that plastic rattle around if bass is playing?