Greetings spy2529,
Looking at some of the other posts, I can tell you that they're partially, correct.
When I started professionally installing sound systems in vehicles in 1983, I didn't find many cars that suffered from sympathetic vibrations because the systems simply weren’t as sophisticated as today. To be quite clear, the systems aren't as sophisticated today as they were ten years ago. We've gone backwards.
I commonly did show vehicles designed for â€Sound-off Competitionsâ€, and these had many sympathetic vibration issues.
“Filling your whole door panels with that foam-in-a-can stuff†won’t solve many issues. If you were to perform this procedure, the vibrations would still be so great that the surface of the hardened foam would de-bond from the inside surface of the doors or body panels, and cause exponential db (Decibel) rise. You would really hear it outside and, in!
As for the “Dynamat spray stuffâ€, in order for it to work correctly, it would need to be so thick, that it would be scraping on the road, and there wouldn’t be much room in the trunk or the cab. I think what result you’re wanting, is rigidity.
Cutting a whole in the rear deck, into the cab of the vehicle, will, allow a considerable amount of restricted pressure to escape and not aid you in the hunt for those nasty buzzes all over, in and under your car.
The size of your enclosures means nothing when it comes to vibrations.
“Sound is subjectiveâ€. It’s what you like, not what someone else thinks you should like.
Like ‘Jays97sho’ mentioned in his post on Aug 12 2004, 05:11 PM. What we’re saying is, if you really desire to rid yourself of these, you’ll have to tackle them ONE by ONE by ONE in layers.
“Striping the car down†is a real good idea. Only remove what can be replaced within a forty five minute period. “Dynamating everything in the process†may not be the only thing that you’ll want to do. As for Dynamat, it peals away from what it’s sticking to, no matter how well you prepare the surface. What I’ve always done is start with the obvious, and then inside the cab, and work out.
Now, if you read all the way through this long post, I’m now going to give you, and everyone reading this, the way I have found all of the vibes in all of the show cars I’ve done. If you have access to a tone generator, with a sweep capability, you can find all of the vibrations at any frequency by connecting it where your head unit is. Now if you don’t have access to a tone generator, you can go to the music store and buy a ‘TEST’ CD. These will give you a generated sweep from high to the lows where you’re having problems. You’ll want to disconnect your other speakers other than the woofs. You don’t need them on blasting you as you’re inside listening for the offending buzzes and rattles.
For your license plate, run a few beads of silicone on plastic rap, the dimensions of your plate, let harden, and place between the license plate ring and behind the plate and body with a thin coat of silicone for adhering the hardened pieces to the plate. This same procedure works well with most parts of an auto. It’s so much lower in price, and more customizable.
I hope this helps.
Tim
P.S: If the Bass sounds better the way you had them before, put them back. What sounds better counts much more.