Trunk Noise
 

I tend to flip flop around with my car projects but I'm wondering about soundproofing the trunk. I've been experimenting with my exhaust to reduce the drone and yet keep the benefits of a 2 1/4 exhaust. I did try sound deadener along the trunk and it helped a little.

But the biggest issue is the exhaust sound coming through the trunk and into the cabin. Theres not too much to absorb the sound in the cabin and the weather stripping on the trunk seems fine.

What I notice is that a large amount of the sound is coming from the speakers and the rear window just amplifies the sound- good for bass, not good for exhaust drone.

So I'm wondering if I could box the rear speakers to seal them off from the trunk without having an adverse affect on the bass quality. I know sub enclosures are specially designed for certain frequencies.

Any ideas on what to do?

Thanks

building boxes for the rear speakers, would probably help the bass response more than hurt it. and it may help keep some of the noise down.

Ok. I was thinking that it was design so that the trunk was basically like a sub enclosure. I guess I shall build a box around them. Is there a certain size or formula? I know certain frequencies are calculated with speaker boxes.

This would just be a 5 sided box mounted up under the speaker on the trunk side.

your not trying to sustain any kind of substantial bass. just a box that fits around them should suffice. I dont think they are getting anywhere near enough power that you would have to worry about heating issues.

Ok. Ill try it out. Thanks.

for sound barriers, you can add MLV. i show this at the end of this thread:
https://www.hondaaccordforum.com/for...e-32679/page8/

MLV + a decoupling barrier is what you use to block sound from the floor.

Beautiful, thanks. I will look into this.

I tried boxing off the speakers using a quick prototype but it significantly reduced the bass and did not keep the sound from coming in the cabin. I will be doing the floor I think but the biggest problem is the noise entering from the trunk. But I think the back panel should be reinforced with some MLV and then sealed.

The noise reduces noticeably when I open a window if that gives you an idea of whats happening. Not many soft spots to absorb sound in the cabin.

A quick update. I looked into this and found that quickroof basically works like automotive mlv. A lot of good reviews about it being used as sound deadener and so much cheaper. $16 for a roll. Ill try that out and update this.

MLV has to be decoupled from the floor to work - that means something soft between the layers.

Ok. I have soft sound deadener in my trunk. (I wasn't sure what I was doing when I put it in). Could I put quickroof over that or the other way around? I've seen quickroof and dynamat placed on the hard metal surface. Isn't dynamat MLV?