Sound deadener, car doors and best practices... wanting to root out t

[altoncustomtech 773]

I've been working with sound deadeners for years. I've tried everything that wasn't a true sound deadener all the way up to Dynamat Extreme, RaamMat BXT and Second Skin over the years and have seen, read and tried all sorts of application theories.

I'm getting ready to tear into my JImmy and have been trying to consider the best course of action where the doors are concerned. Like the way Don and Aaron worked on Aaron's car and used the SDS products for a complete and total noise control system is my end goal. I have gathered quite a bit of CLD and CCF for the install and when the funds become available I'll be purchasing the MLV I need to complete it.

What I'm trying to find out is on the treatment of the doors. I learned of and liked the results I got from the much used way of doing the doors in the past where a person takes some flashing material, perforated metal, plexi or plastic and covered all the big holes in the door then covered the entire surface with CLD. The results from doing that were usually quite nice with much improved bass response from the door speakers. However, I can also see how the MLV and all it's mass would also be quite effective at keeping the back wave under control.

So, what is the best way to handle the doors? Do both? Don't worry about sealing all the holes? What is the best way to proceed with this task now since 25% CLD coverage is basically all that's needed?

[Second Skin Rep Jon 17]

Personally, this is how I would approach it.

Start with 25% coverage and see what the resonance level is at this point and bump the coverage up to a MAXIMUM of 50% if need be. I just recently tackled an AC unit and ended up going with 30%-35% panel coverage, took some time and effort but well worth it.

Add the MLV inside the door to help block the outside noise as well as combat the rear projected sound waves. It may be difficult to get the MLV in there, but well worth it.

Sealing off the door cavity with sheet metal/perf metal/plexi... I'm a fan of doing this because it always seems to improve the SQ and bass response of the door speakers. Of course always cover the openings in a way that is reversible.

That's my opinion.

[altoncustomtech 773]

That's pretty much what I was looking for and pretty much the way I've been used to doing it like I mentioned, except for the MLV. I'm looking forward to the improvements the MLV makes as well. Glad to see an answer too, I'm starting on the doors tomorrow.

[Rudeboy 152]

I've come to a different conclusion. Keep in mind that I've always built access hole covers in the past. I'm pretty much convinced that the layer of MLV on the inner skin does everything the covers did, with the other benefits, or at least so close to what the covers did that it doesn't seem to be worth the effort. I put access hole covers in the "a lot of work for the possibility of a very slight improvement" category. Belt and suspenders.

[Aaron Clinton 2,372]

I was spoiled during that process, as I was able to turn to Don and say what about here and how much and why.

[Second Skin Rep Jon 17]

LOL, totally unfair!

[altoncustomtech 773]

I've come to a different conclusion. Keep in mind that I've always built access hole covers in the past. I'm pretty much convinced that the layer of MLV on the inner skin does everything the covers did, with the other benefits, or at least so close to what the covers did that it doesn't seem to be worth the effort. I put access hole covers in the "a lot of work for the possibility of a very slight improvement" category. Belt and suspenders.

Ding, Ding, Ding!!! Thank you Don!

I had some theories, which is why I made this thread, to help pan out my thoughts, theories and the facts. I've always liked what covering the holes did to help the sound. Though on the same line of thought I couldn't help but come to the realization that it would seem that a layer of MLV would or could negate the need for "sealing" up the door in the first place as long as it was properly deadened in the first place. It just kind of made sense and staring down the fact I was going to be doing this very soon (began yesterday as a matter of fact) I was really hoping it would work out that way. It makes for less work and will definitely help with a couple of other concerns I have with a window motor that's possibly looking for replacement.

Thanks again guys, I think you're all a bigger help and asset than you realize.

[Micksh 16]

Thanks guys for the informative topic...I don't think many people realize what a difference sound deadening can have on your system...everyone thinks about the rattles and things from the sub-bass, not many think about the effect on midbass/midrange and just the overall road noise and sound improvements that can be had. It's sometimes an overlooked part of the system, just as alternators and batteries always were until the push for high SPL numbers became big...thanks again!

[///M5 2,833]

I've come to a different conclusion. Keep in mind that I've always built access hole covers in the past. I'm pretty much convinced that the layer of MLV on the inner skin does everything the covers did, with the other benefits, or at least so close to what the covers did that it doesn't seem to be worth the effort. I put access hole covers in the "a lot of work for the possibility of a very slight improvement" category. Belt and suspenders.

Ding, Ding, Ding!!! Thank you Don!

I had some theories, which is why I made this thread, to help pan out my thoughts, theories and the facts. I've always liked what covering the holes did to help the sound. Though on the same line of thought I couldn't help but come to the realization that it would seem that a layer of MLV would or could negate the need for "sealing" up the door in the first place as long as it was properly deadened in the first place. It just kind of made sense and staring down the fact I was going to be doing this very soon (began yesterday as a matter of fact) I was really hoping it would work out that way. It makes for less work and will definitely help with a couple of other concerns I have with a window motor that's possibly looking for replacement.

Thanks again guys, I think you're all a bigger help and asset than you realize.

Pretty easy to seal the holes with a removable panel....even better if you use something heavy like MLV for sealing the holes. A few rivets and some green tape and its just one more layer to make sure things are right.

[Rudeboy 152]

I've come to a different conclusion. Keep in mind that I've always built access hole covers in the past. I'm pretty much convinced that the layer of MLV on the inner skin does everything the covers did, with the other benefits, or at least so close to what the covers did that it doesn't seem to be worth the effort. I put access hole covers in the "a lot of work for the possibility of a very slight improvement" category. Belt and suspenders.

Ding, Ding, Ding!!! Thank you Don!

I had some theories, which is why I made this thread, to help pan out my thoughts, theories and the facts. I've always liked what covering the holes did to help the sound. Though on the same line of thought I couldn't help but come to the realization that it would seem that a layer of MLV would or could negate the need for "sealing" up the door in the first place as long as it was properly deadened in the first place. It just kind of made sense and staring down the fact I was going to be doing this very soon (began yesterday as a matter of fact) I was really hoping it would work out that way. It makes for less work and will definitely help with a couple of other concerns I have with a window motor that's possibly looking for replacement.

Thanks again guys, I think you're all a bigger help and asset than you realize.

I've been doing this for enough time to have tried every excessive and unnecessary thing that can be imagined Three questions help avoiding the mistakes I've made:

1. Do I REALLY need to pierce or cut sheet metal?
   
2. Do I REALLY need to make the sheet metal inaccessible for future body work or make vehicle components inaccessible for future maintenance?
   
3. Do I really need to install this stuff in such a way that removing it to deal with 1 or 2 will destroy it and leave me starting from scratch?
   

It's amazing how seldom the answers to any of those are yes. I've told this story before, but it applies. I share a building with a body shop. The guys there have taken a strong interest in what I do. I had just finished lining a trunk with CCF and MLV and they came over to check it out. One of them said: "That's great, but what if you're rear ended - how do we get through all that?" I reached in, unhooked some Velcro, pulled it all out in one piece and dropped it on the floor. Took less than a minute. They cheered

The sound deadening version of the Hippocratic Oath is: Make no permanent alterations to the vehicle that don't absolutely need to be made.

[Notorious97200 339]

I like this topic.

Very informative.

SSA rules !!!

Thanks guys !

[mccleery3 166]

Looks like I'll be picking Don's brain in a few months for suggestions and info concerning my Suburban

[sefugi 166]

Great info!!!! Very informative insite from those who have been there and done that!!!