Sound deadener placement advice

[Marve_Lous]

So I just got my sound deadener today and will hopefully get a chance to put it on tomorrow. I’ve never installed sound deadener before so I’ve searched YouTube videos and see some people covering every square inch and some people just kind of patching different places. I want to focus on my trunk lid since it rattles the most so any advice on placement and what I should and shouldn’t cover or need to and don’t need to cover would be much appreciated. Here’s a pic of my lid if that helps:

 

[SlugButter]

I would do the whole trunk lid

 

[SlugButter]

Doors are where you can kinda get away with strategic placement, although doing the whole door panel is for sure the best way.

 

[Marve_Lous]

I would do the whole trunk lid

So 100% for the lid? Even out to the edges beyond the factory lining? Here’s a pic with the lining.

 

[SlugButter]

Nah. You wouldn’t need to go beyond the factory edges if looks are important.

 

[mastershake575]

So I just got my sound deadener today and will hopefully get a chance to put it on tomorrow. I’ve never installed sound deadener before so I’ve searched YouTube videos and see some people covering every square inch and some people just kind of patching different places. I want to focus on my trunk lid since it rattles the most so any advice on placement and what I should and shouldn’t cover or need to and don’t need to cover would be much appreciated.

The people who do full coverage do it for 2 reasons

1. They are using low quality deadener that has weak properties. They think there saving money by buying cheap deadener but if you have to apply 3x as much to get the same acoustical deadening properties then your not really saving money

2. They think deadener blocks sound which is doesn't. It helps prevent the panels from vibrating (reasonance) but it doesn't actually block noise. They think "oh if I do full coverage i'll block the noise from coming it" when it doesn't work like that. You need something like MLV

In regards to your trunk if your using a high quality deadener then at least half coverage should be fine. You eventually get to the point of diminishing returns. Think of it like a drum cymbal, if I apply 25% coverage to the cymbal and then hit it with the drum stick the cymbal will hardly make any noise. Me adding 75% more coverage to that same cymbal might make it 5% quitier if even that

 

[Marve_Lous]

The people who do full coverage do it for 2 reasons

1. They are using low quality deadener that has weak properties. They think there saving money by buying cheap deadener but if you have to apply 3x as much to get the same acoustical deadening properties then your not really saving money

2. They think deadener blocks sound which is doesn't. It helps prevent the panels from vibrating (reasonance) but it doesn't actually block noise. They think "oh if I do full coverage i'll block the noise from coming it" when it doesn't work like that. You need something like MLV

In regards to your trunk if your using a high quality deadener then at least half coverage should be fine. You eventually get to the point of diminishing returns. Think of it like a drum cymbal, if I apply 25% coverage to the cymbal and then hit it with the drum stick the cymbal will hardly make any noise. Me adding 75% more coverage to that same cymbal might make it 5% quitier if even that

I see. I bought Second Skin Damplifier Pro. I hope that’s not the low quality stuff. And I don’t care about the sound coming out. I just wanna reduce the rattle as much as possible.

 

[mastershake575]

I see. I bought Second Skin Damplifier Pro. I hope that’s not the low quality stuff.

No that's high quality stuff. 80mm american sourced butyl with no fillers. Great choice, your not going to have to paint it on like you would something like fatmat or noico

And I don’t care about the sound coming out. I just wanna reduce the rattle as much as possible.

Yeah most of the noise we hear while driving is the panels resonating (aka rattling). Deadener on doors and trunk makes a gigantic difference

 

[metalheadjoe]

In my experience, deadener alone won't stop exterior rattles. I'd try to beef up the trunk seal to make it close tighter.

 

[fixinit]

So I just got my sound deadener today...where should I put it.

It's an easy answer. The raised sections of your trunk are thicker than the flat parts. You can tap your knuckle on different areas to test---lower frequency tap means more resistant vibration quality. Anyway, cut out some small pieces over the flat spots on that trunk. No need to be precise here, but quality cuts look better down the road. 5 panels look like a good start. Let us know if that helped. Here's my coverage of an asphalt based liner. It works but I wouldn't do this to my newer vehicle.