i was running 2 mojo 15s in a wall on a memphis 4kw.

as far as sound deadening there are many kinds you can use....fatmat, hushmat, edead, raamatt, secondskin etc. im using a combination of fatmat and hushmat and it works great

 

did you just layer the fatmat and hushmat ontop of each other? I think im gonna need a lot to build up my roof

 

Sorry to go off-topic but, wouldn't deadening the vehicle change the resonant freq? Also, how would one go about finding the resonant freq? Just make a track going from like 20Hz up to 70 or so and stop when it gets loud?

 

correct you are. I guess my order was not correct. I wasnt writing as the order of events though. haha. But yes, deaden first, then find the resonant frequency. The way you mentioned is the "poor mans" way of doing it, but there is professional test equipment that will do it for you. Never had it done so I dont know the details.

 

in order to find the resonant frequency of your truck you need to first find someone with a termlab that will either let you use it or do it for you. You then play a sweep from say 40hz-70hz and the termlab will show you where your peak is on the truck

 

Thanks guys, I figured you would sweep through the frequencies but wasn't sure how you'd figure out exactly what freq is right.

 

aww off topic. I just kidding. so deaden the hell out of my truck. I would uyuse sement but its my everyday driver. gotta worry about that mpg. lol. thankfully I know someone with a meter. so finding my frequency shouldn't be too hard.

 

weight is the whole point of deadening. Mass loading a surface to lower its resonant frequency. That is the definition of deadening lol. Kind an oxy moron to say you are worried about weight, yet you are still mass loading. lol

 

that is very true. haha. well im worried about weight when it comes to cement vs. fatmat/hushmat. lol.