sound deadening - which to get ?

[Dblock]

I have dynamat on big flat panels, this is to absorb rattles - not to block sound. I also have luxury liner pro lining my doors and boot etc. This is to block sound from outside. It does weigh a bit but it takes mass to block low frequency sound waves from outside. I read a comment about studios having egg box foam, this is to stop reflections, nothing to do with blocking sound. This would be done with a lead liner in the wall AFAIK.

 

 

Thank you mate Also the luxury pro liner is that a barrier or just deadening?

[ikarus]

Luxury liner is a barrier. It has a heavy vinyl layer bonded to a foam layer which acts as a decoupler. The heavy layer blocks low frequencies such as road noise, truck engines etc. The foam layer acts like a diffuser, scattering higher frequency sound waves. The two layers together do a good job of blocking out a lot of outside noise. I looked into all this before I did mine, that's how I remember it anyway

[Dblock]

Luxury liner is a barrier. It has a heavy vinyl layer bonded to a foam layer which acts as a decoupler. The heavy layer blocks low frequencies such as road noise, truck engines etc. The foam layer acts like a diffuser, scattering higher frequency sound waves. The two layers together do a good job of blocking out a lot of outside noise. I looked into all this before I did mine, that's how I remember it anyway

 

cheers mate thought about doing that myself.

[H5]

Isn't dynamat expensive and very heavy?

 

 

Yes and kinda. There are cheaper things out there which do a better job. Its kinda heavy. Sound deadening needs mass for it to work. On my clio I had 4mm loudboy stuff that was heavy.

 

Original quote - expensive is a reflection of value and weight is relative. So no would be my answer.

I really don't get why people on here get into these cars and then advocate cutting corners each time they mod something....

 

And sound deadening does not need mass for it to work. Why are studio walls covered in 'egg box' foam? It needs a pattern and / or material to absorb the frequencies. It also depends what the resonant frequency of the material you are applying the deadening to. Check some of the simple tests you can see where a 1" square piece of Dynamat Xtreme renders a cymbal complete tuneless vs some of the other 'bargains' out there.....

 

 

Not really second skin isnt as expensive as dynamat nor is slient coat. Getting a better product isnt cutting cornors, dynamat just isnt that good. Loudboys 4mm stuff is great and cheap.

 

here is pic of his 4mm stuff vs damplifier pro

 

the 4mm stuff was used in my clio running a RE XXX 15" port tuned to 32hz. It was silly loud as it was facing the up so I got the horn effect aswell. No pannel ratttle. He also does a 2.5mm foil backed one.

 

If the doors where about 3 metres thick then yes soft absorbing materials are great but you dont have that option. Mass is generally the best way to stop panel rattle and sound deaden the areas. In a boot you could have a sub box and on the sides stuff it with towels. this does a great job of stopping vibrations but you cant do that on a door.

 

Also as Rob has said I personaly never found flashing tape to be great but that doesnt matter its messy. If your car is in the sun and you roll down the windows sometimes they get stuck and you get the glue on them. Personally in the last 12 months I havent seen anyone do anything with flashing tape. Generally its considerered crap.

 

All IMO of course.

 

So you managed to get it to stop noise at one frequency (ported tuned box to a particular frequency) - that doesn't mean it has sound deadening properties across a range of frequencies / volumes.... Having done SQ to Ultra level I have heard the differences. Albeit a huge part of the benefit of Dynamat Xtreme is the places you can get it. Just not sure why if the stuff is so good it isn't outselling Dynamat......??

[Dblock]

Isn't dynamat expensive and very heavy?

 

 

Yes and kinda. There are cheaper things out there which do a better job. Its kinda heavy. Sound deadening needs mass for it to work. On my clio I had 4mm loudboy stuff that was heavy.

 

Original quote - expensive is a reflection of value and weight is relative. So no would be my answer.

I really don't get why people on here get into these cars and then advocate cutting corners each time they mod something....

 

And sound deadening does not need mass for it to work. Why are studio walls covered in 'egg box' foam? It needs a pattern and / or material to absorb the frequencies. It also depends what the resonant frequency of the material you are applying the deadening to. Check some of the simple tests you can see where a 1" square piece of Dynamat Xtreme renders a cymbal complete tuneless vs some of the other 'bargains' out there.....

 

 

Not really second skin isnt as expensive as dynamat nor is slient coat. Getting a better product isnt cutting cornors, dynamat just isnt that good. Loudboys 4mm stuff is great and cheap.

 

here is pic of his 4mm stuff vs damplifier pro

 

the 4mm stuff was used in my clio running a RE XXX 15" port tuned to 32hz. It was silly loud as it was facing the up so I got the horn effect aswell. No pannel ratttle. He also does a 2.5mm foil backed one.

 

If the doors where about 3 metres thick then yes soft absorbing materials are great but you dont have that option. Mass is generally the best way to stop panel rattle and sound deaden the areas. In a boot you could have a sub box and on the sides stuff it with towels. this does a great job of stopping vibrations but you cant do that on a door.

 

Also as Rob has said I personaly never found flashing tape to be great but that doesnt matter its messy. If your car is in the sun and you roll down the windows sometimes they get stuck and you get the glue on them. Personally in the last 12 months I havent seen anyone do anything with flashing tape. Generally its considerered crap.

 

All IMO of course.

 

So you managed to get it to stop noise at one frequency (ported tuned box to a particular frequency) - that doesn't mean it has sound deadening properties across a range of frequencies / volumes.... Having done SQ to Ultra level I have heard the differences. Albeit a huge part of the benefit of Dynamat Xtreme is the places you can get it. Just not sure why if the stuff is so good it isn't outselling Dynamat......??

 

People are brand whores simples. It hasnt stopped noise at a certain freq, it adds mass to the panels to stop them shaking. also you think a sub port tuned to 32hz can only play 32hz? damplifier pro, second skin, slient coat are all as good if not better for cheaper. Most people havent heard of them.

[chrisjones6699]

That 4mm stuff. where can that be bought from?

[Dblock]

That 4mm stuff. where can that be bought from?

 

Talk audio, just pm loudboy and tell him dblock sent you

[ikarus]

Are there any guides on here as to where to fit sound deadening, I got a couple of sheets of brown bread and just stuck it in my boot under where the wheel goes made a bit of a hash of it but it still made a difference.

 

I would like to have a go at doing the boot properly and then maybe the doors, ive seen guides on here for removing door cards etc and have searched but cant find a guide to fitting sound deadening, pics would be good

 

Not my work but very useful reference..

 

Doors:

I start with my CLD Tiles which are really just a beefed up version of something like Dynamat Xtreme. They are 6"X10" because I want them to be easy to handle and I don't want people to use too many of them. Since the effectiveness of a constrained layer damper falls off dramatically after 25% of the surface, weighted toward the center is treated, I wanted a damper that would take maximum advantage of that real estate. You can get close to the same result using a little more Dynamat Xtreme. Anyway, 25% coverage of the outer skin, treating the area above and below the side impact protection beams as distinct panels.

 

I then stuff Extruded Butyl Rope, the same adhesive used for the tiles in 3/8" cylindrical form, between the side impact protection beam and the outer skin. This way the doors's own structure can be used for additional damping and to support the center of the large outer skin. Similar products are used for sealing windshields and other tasks so you may find something suitable to use instead. Leave gaps for water to drain through and push some plastic sheeting strips into the exposed surface of the butyl to keep it clean.

 

25% coverage of the inner skins and we are done with vibration damping for the doors.

 

An important step, particularly if you have door mounted speakers is fabricating removable inner skin access hole covers. I've used fiberglass or I'll just cut aluminum flashing, two pieces for each cover and make a sandwich with Extruded Butyl in between. Heating the assembly in an oven will soften the butyl and allow you to flatten it out completely. The result is an extremely non-resonant cover. You can use anything that is rigid, waterproof, non-corrosive and can be formed to follow the contours of the hole's perimeter. I run a bead of butyl around the edge and use self tapping screws to lock it down.

 

Sealing the access holes helps with noise rejection. If there are door mounted speakers it helps reinforce the baffle - isolating the front and back waves from the speaker.

 

Now we need a barrier for the doors. Closed cell foam (CCF) is almost a necessity because of possible exposure to moisture. I use mass loaded vinyl (MLV) but lead or very dense rubber will work too.

 

Most modern vehicles have inner skin access holes that are too small to make attaching the barrier system to the outer skin. In some cases it will be the best option and will take a slightly different approach. I hang the MLV on the inner skin using self adhesive Velcro Patches. This makes the barrier easily removable for future maintenance and easier to deal with as you cut the small oles you will need for cables, shafts and whatever else needs to pass from the outside to the inside surface. You want these holes to be as small as possible and you want the MLV to be as large as it can be while still allowing the door card to fit back on. Gaps and holes are the enemy.

 

Once the MLV is fitted, I glue some CCF to the side of the MLV facing the door card. This is the reverse of the usual barrier/decoupler configuration, but it works very well in the doors. When the door card is replaced, the CCF compresses slightly eliminating rattles and buzzes in the door card and between the door card and the inner skin.

 

Doors done.

 

Everything else is much simpler. For the floor, I'll usually rip the stock vibration damper out if it is asphalt (bitumen). In a car that is more than a few years old it is usually crumbling anyway. In any case, asphalt is such a miserable vibration damper that I won't have it in my own car or any car I work on. I always curse the OEM as I pull it out.

 

Same drill with the vibration damper - 25% coverage of the open, unsupported areas. Stay away from the edges of panels, bolt down points, welds and sharp bends. Tapping is a good way to determine which areas are most resonant, but it is not a good way to determine when you have added enough vibration damper. It doesn't replicate any real world conditions and you will basically add vibration damper until it is thick enough to insulate the tap from the sheet metal. One layer, 25% coverage, done.

 

I use 1/4" CCF on the floors if it will fit and it usually does. In most cases you only need to lay it on the bottoms of the floor pans. It's great if you can run it at least partway up the center tunnel and the sills, but trim panel replacement usually makes this impossible. You will be able to run it up to the stock barrier on the firewall and it's a good idea to do so.

 

Follow with the barrier material. This should be run up and over the tunnel, up into the kick panel area, up the sills, as far up the firewall as you can reach and basically anywhere you can get it. Again, you will need to cut small holes for the seat bolts and seat belt anchors. Keep them small. Seal all seams. Gaps in a barrier work the same way an open door into an adjacent room does - sound comes through.

 

Don't use adhesive on the floor unless you absolutely have to. The carpet, trim and gravity will hold everything in place. Gluing the stuff down doesn't improve performance in any way and will make your life miserable if you ever have to get under the material.

 

You can follow the same procedure for the boot, cargo area, wheel arches or whatever you are dealing with. Enough vibration damper to stop resonance and a CCF/Barrier layering to block sound. On complex surfaces you will need to do some cutting and pleating to get things to fit unless you are using lead.

 

You don't need a barrier on the roof, but I like to apply vibration damper and cover it with a layer of CCF. Air turbulence and weather noise will be much reduced.

written by Rudeboy, Talkaudio

http://www.talkaudio.co.uk/vbb/showthread.php?t=306859

 

I might be able to find out some photos of my 350z door and boot install if anyone wants to see. I used Dynamat Extreme and Luxury Liner Pro. If there is interest i'll post them.

[neo]

^^ photos of the boot and door install would be very useful to everyone i think

[ikarus]

Doors were easy enough..

 

You just need to get the door card off and the electric window cover to get access to the outer panels. You have a side impact bar right across the middle which is the only pain though.

 

Bare door, lots of flat panel to resonate!

 

one layer of dynamat extreme takes care of virations..

 

and one layer of luxery liner pro decoupled on top takes care of blocking road noise..

 

Dynamat is adhesive, just goes on with a small roller, i cleaned up the metal skin first to make sure it would adhere. The Luxury Liner is just spray glued on top of the silver backing of the Dynamat. Simple.

 

More later.

[ikarus]

Fibreglass door pod builds..

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[ikarus]

and fibreglass A pillar builds..

 

Stock A pillar

 

Position located for tweeter

 

 

 

 

A little fabric for shape

 

 

Fibreglassed ready for filler and finish sanding once fully cured

 

Choice of vinyl against original plastic finish..

 

Trimming in action, this was the pain stage..

 

One finished..

 

..and fitted..

 

 

Front end all finished, months of work and you can barely tell (exactly what i was aiming for)..

 

 

 

More pics from the midbass and rear install when i get more time

[H5]

Here's mine

 

[H5]

Link to my install thread....

 

viewtopic.php?f=27&t=13074&hilit=install

[H5]

And nice work Ikarus

[ikarus]

And nice work Ikarus

 

Likewise, great use of boot space while retaining the spare

[Dblock]

Ikarus thats sweet. When you making some a pillars for me? Nice install though alot of work has gone into aiming.

[neo]

thx guys, a lot of work as gone into both Z's

[H5]

After having competed and had a system capable of so much I still wanted the sound but went stealth. Although there are times I kinda want to show it off....!!

[neo]

still not got round to ordering deadening yet, think my headunit is dying so will wait a little while longer

 

did find a bargain of a roller instead of £9.99 at some audio shops i got a roller,scissors, knife and scraper for the huge amount of £1 from my local poundland, guess some of you wouldn't even dream of setting a foot in any pound shop but you'd be amazed

[andlid]

Kudos for all that work mate