Dynamat?

[rgplayer 10+ year member]

I have an 03 eclipse and 2 rd sonance 12's in a 3.5cuft box at 35 htz. I have an audiopipe 1500d amp, and a Kinetik hc600. I have no sound deadning and I have took my trunk plastic out many times, so I'm sure it's not sealed as good as it was factory. In the the trunk on the passenger side down in the fender there is a flap like thing that opens when there is any kind of pressure difference, even the slightest will cause it to open. I'm estimating but it looks like it's about 10 inches long and 3 or 4 inches wide, and is pretty much an open hole outside. I sat in my friends car which is an 03 couger, tonight that has 2 12 type r's in a prefab box and a crossfire 1000 watt amp, that he had professionally installed. He doesn't have any deadner but also I doubt it has that huge hole, also the plastic hasn't been removed none besides if the shop did it. His car seemed louder to me, but for some reason the car isn't flexing much at all, but I know that may just be because of the different build of the car. I'm sorry for the wall of text, but my question is if I deaden everything and fill that hole will it make a pretty big difference?

Click to read more...

 

[bass_lover1 10+ year member]

If you ever want to shut your doors easily again, I don't recommending sealing that hole.

 

[rgplayer 10+ year member]

I'm not sure what it does, could you explain please? Will the dynamat help though? Thanks.

 

[Marlo Stanfield 10+ year member]

I am soo confused at what you're even asking with this thread... I read through it a couple times to try and help, still can't figure it out.

 

[rgplayer 10+ year member]

Just wondering why his car seemed louder to me , but my car is flexing a lot more. Will dynamat help seal the trunk, because there is a lot of air escaping from the large air flap in my trunk.

 

[Marlo Stanfield 10+ year member]

Yea it should help, give it a shot... The more you can reduce flex the louder your system will get. The more sound that stays in the car the louder it will seem.

you

Also the only electrical u have is a Kinetik 600 on the AP 15001@1ohm?? I'm guessing that you are getting pretty decent voltage drops so that will play a part. Also you may be getting sum nasty imp. rise, that plays a factor also.

 

[dadydolas 10+ year member]

A lot of things could make his vehicle louder. The simple answer is it may help but you will have to try to find out.

 

[rgplayer 10+ year member]

Yeah my voltage drops to like 12.5. I'm not sure what imp rise is or how to reduce it?

 

[bass_lover1 10+ year member]

I'm not sure what it does, could you explain please? Will the dynamat help though? Thanks.

The pressure that is created when you shut a door/hatch needs to go somewhere, that flap is what equalizes the pressure inside the cabin to the outside air pressure. You can cover it, but like I said it's going to be a bit harder to shut your doors if you do.

Dynamat will help. To step flex you need to add mass, which is exactly what stuff like Dynamat does. However, there are a multitude of choices as far as mass loading products goes, Dynamat is a good one, but it is expensive when compared to similar products.

Sounddeadenershowdown.com is a good place to start, you don't necessarily have to buy from him, but at least read up on the products he sells and what they do.

 

[duece212 5,000+ posts]

I covered the cab vents in my truck and it didn't really make a huge difference in shutting the doors, it did make a big difference when using the heater/ac though. The truck would pressurize enough to mess with your ears. I always had to crack a window whenever the heater/ac was on.

Cover it and see if it makes a difference, doubt it will make much difference to how loud you perceive your system to be. If it doesn't make a big difference open it back up, its not worth the hassle of having to crack a window or put your vent on recirculate if its closed off.

 

[rgplayer 10+ year member]

My weather striping in the hatch is terrible also. I can feel so much air coming out of the hatch, it's bad. It leaks down into the tire well, luckily I have the amp behind the box, the box can't get wet or anything but that kinda show how bad the weather stripping is. I am guessing that 75% of the car flexing is bad too.