Major rattling and loss of bass.
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=64172
Printed Date: April 29, 2024 at 7:48 AM
Topic: Major rattling and loss of bass.
Posted By: pimpincavy
Subject: Major rattling and loss of bass.
Date Posted: October 10, 2005 at 11:26 PM
Me and my friend built a ported box for my Kicker CVR 15 and installed it (running off a JBL 600.1) over the weekend. It sounds really good, except for some major rattling issues. Its mainly the trim piece below the tailights, and sometimes the whole tailight assembly. Ive heard some bad trunk rattle before, but this is about the worst, its can be clearly heard inside the car, and is very loud outside of it.
These rattles only occur on certin bass notes. When the trunk rattles, there is almost no bass produced into the car, while on other notes where the trunk does not rattle there is ample bass inside the car. Would some soundeadning on the rear of the trunk help stop the rattle? If so what would be a inexpensive sound deadner that I could put on myself?
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Replies:
Posted By: palouse md
Date Posted: October 11, 2005 at 2:45 AM
there are several sound deadening materials, my prefered is the Dynamat Extreme. easy to install but it is not cheap. very effective, very easy to install, works wonders. NO MORE RATTLES!!!!!! GOT BASS?? ------------- MD
Posted By: alpine_king
Date Posted: October 11, 2005 at 12:52 PM
is there any way you could tighten up the trim peice? like any nuts on the inside of it or anything?? also check the tail light screws and tighten them up. ive seen ppl stuff old socks and stuff up into the top of the trunk, and it kinda takes the rattleing away, but if you want it gone for good, go get some dynamat.
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1993 Ford Ranger.
Head Unit.Alpine CDA-9831
Front Speakers.Infinity 6010 Reference Series
Amp.Alpine MRD-M1005
Subs.3 Kicker CVR10
Rear Speakers.SPL CS-573
20" Boss 312's, lowered 3/4
Posted By: sneakycyber
Date Posted: October 11, 2005 at 2:09 PM
The reason why the car rattles and you do not hear much bass is because you are acheiving the resonant frequency of the vehicle. In other words the whole damn car starts vibrating.
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Posted By: pimpincavy
Date Posted: October 11, 2005 at 10:23 PM
No there arent any screws or bolts on the inside of the trunk for these panels, except for the screws for the lights. Ill try to tighten those up. Yes the whole damn car does start vibrating at some bass notes. Will sound deadning help this, or is it unavoidable? Im going to stop at my local car audio shop and have them look at it, and price out dynamat. is there anything cheaper out there, ive heard of brownbread and edead, but I dont know where to find them, or if they are recommended.
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Posted By: rudeman
Date Posted: October 12, 2005 at 7:07 AM
sneakycyber is exactly right. You are hearing rattles because your car is resonating and you are losing sound pressure because the sound energy is being absorbed.
You need to address both the rattles and the vibration. Find the rattling parts and isolate them from whatever they are rattling against with foam or something similar.
To stop the resonating panels, you will need to apply a dampener, like Dynamat, but here are many alternatives. The link in my sig has a review of several possibilities. Sound deadening has the added benefits of reducing road/engine/traffic/wind noise and improving SQ inside the vehicle.
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Don Sambrook
Posted By: stevdart
Date Posted: October 12, 2005 at 7:58 AM
Good article you've written, Don. If anyone reading this has passed that link above without clicking it, go back and open it and save it...there's a lot of good information there. It's amazing how much time and money a lot of guys spend on things (like new subs, extra midbass drivers, caps, new amplifiers, etc etc.) to make their system sound better when proper damping hasn't been done. They just never achieve the potential without it.
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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
Posted By: rudeman
Date Posted: October 12, 2005 at 9:35 AM
Thanks very much! I'm about a week from a completely new version - tests that come a lot closer to real world conditions and I've added B-Quiet and Brown Bread.
When I wrote the current version, it was mostly for my own information - I thought maybe 20 or 30 people would ever see it. After a month and a half, more than 2,000 have read it. People have sent me all sorts of data and experiences and that will be reflected in the next version.
Thanks again for the kind words.
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Don Sambrook
Posted By: Asmodeus
Date Posted: October 12, 2005 at 10:11 AM
For trunk rattles I have always had success using Expanding Foam You can get this stuff at Wal-Mart Called GREAT STUFF....Its an expanding foam....So anywhere that your trunk has rattles that would not be seen you can spray this stuff in and when it expands it gets hard as a rock.... Usually in a car I spray it in the support rails on the inside of the trunk to stiffen the trunk lid....Just be sure not to get this stuff on your carpet or anything else you dont want ruined its very sticky and makes a mess....I would suggest a drop cloth to cover anything you want to keep.... Also behind your lights....Just drill a hole to get behind them from the inside of your trunk behind the trim pannel...Then just spray the foam in ....It should stop the rattles... THIS IS NOT A DEADING MATERIAL....Simply tightens up places that rattle...I would still suggest a deadening material such as Dynamat or Brown Bread.... Hope this helped... -------------  Making the World A Louder Place
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