Home Brew Sound Deadening +

Sub and Amp Install.  Outline and Theories.

I started at the top, with the roof, and used standard carpet underpad.  I used various types of sealants for glue and the one I was most happy with was cheap silicone, however, you have to let the vehicle air out for a long time.  Do NOT use any butyl products like acoustiseal as they don't dry and you may have a big mess to deal with.  I used a lot of sealant, upwards of 40 tubes, maybe more; 4-5 tubes in each door for example.  There are several properties of the different products being used that play a part in the sound deadening.  1; the mass of the sealant reduces resonance by adding weight to the panels.  2; the elastomeric properties of the sealant, by nature, reduce resonance.  3; sound absorbing properties of the foam and it's surface textures.

I started at the top and worked down; Did a complete layer across the roof, including the cross-member, then another layer, both in front of the cross-member and behind it; you may be able to make out the darker area in the rear section.  The headliner barely fit back in the truck; it barely goes behind the inside trim, but the main thing is, it does.  :)

Unfortunately, I didn't take any pictures of the door process.  The foam I used for the doors is a closed cell polyethylene carpet underpad I got at Home Depot.  Closed cell foam must be used where there is a possibility of getting wet so mold and mildew doesn't grow in the foam.  A good time to do the doors is when you are changing the speakers, as you can use the speaker hole as an access point.  Cut the foam in chunks that fit into the holes easily, roughly 6"x6", paste with sealant and proceed to cover the inside of the door panel.  I put a second layer of foam, about 12"x12" area directly behind the speakers for added dampening.

This is the rear cab area, with rear seats removed and carpet lifted.  The floor got 1 layer of the closed cell foam.  I removed the air vents from the back panel and sealed up the holes with some acoustiseal and some 20 gauge galvanized sheet metal and self tapping screws.  The back wall got a layer of open cell foam first and then a second, smaller layer of closed cell foam.

Finishing up.  The subs are Pioneer TS-W256C, single voice coil, 4 Ohm, 350 RMS and I built my own boxes to custom fit in each space.  One amp is screwed to the back panel of the cab and the other, I welded up a bracket, that bolts to one of the seat mounts and uses a self tapping screw on the other side and attaches to the 'jack bracket'.  I had to use extensions for the seat-backs, to give a bit more room for the sub enclosures; the extensions are about 2.5".  Also, the hooks on the backs of the seat-backs, need to be trimmed but only if you want to fold the seats down without removing the bottom bolts... otherwise, just remove the bottom bolts from the backs of the seats and pull the backs out normally.

Copyright 2006