Sound dampening

[natsoundup]

http://www.thezeb.com/caraudio...rture

The inexpensive site for Dynamat products

[maxnix]

Might want to consider Soundcoat also. They have been around for decades and have materials appropriate to underhood environments also.

[aemikeg]

you know... it's sound DAMPING not DAMPENING. Unless you are trying to get your music wet :-)I use scosche accumat. you guys get it for $15 a sheet plus freight (24" x 27" or about 4 sq ft) It's light and moldable. You still need a heat gun and some acetone to clean the metal but it works well.

[diamondj30]

oh well.

[Highway Q45]

As previously mentioned the visciolastic material from McMaster-Carr Supply Co. is a killer deal for the same results as Dynamat. It's not as pretty but you can cover every square inch of a Q for a lot less. Another option I've used twice now is a non-bituminous roofing patch. It's sold at roofing supplys and is made by Polyken of 35 mil butyl rubber core, aluminum facing, and release liner. It has no odor, very formable, and works great as a heat barrier. It comes in 6" and 8" wide rolls-50' long for about $12-$16. Dynamat is for good but the price is absurd!

[diamondj30]

thanks

[brucepelletier]

As previously mentioned the visciolastic material from McMaster-Carr Supply Co. is a killer deal for the same results as Dynamat. It's not as pretty but you can cover every square inch of a Q for a lot less. Another option I've used twice now is a non-bituminous roofing patch. It's sold at roofing supplys and is made by Polyken of 35 mil butyl rubber core, aluminum facing, and release liner. It has no odor, very formable, and works great as a heat barrier. It comes in 6" and 8" wide rolls-50' long for about $12-$16. Dynamat is for good but the price is absurd!

That's quite a deal compared to Dynamat. Could you expand on your personal experience with installation and performance? This sounds like the best option yet.

[brucepelletier]

http://www.thezeb.com/caraudio...rture

The inexpensive site for Dynamat products

Thanks for your response with web site.I checked out this site briefly. So many options and choices for material and applications. What would you recommend for sound damping in a Q? I'm very interested in your informed opinion.

[natsoundup]

I am still doing research....everything seems to point to Dynamat Extreme.... I have two cars to do...so I will buy the bulk pack....36 sq feet..

[Highway Q45]

Bruce,I have tried the McMaster-Carr sheets (36"x40"x.062" thick, Part # 9709T21 @ $18.08/sheet) It works OK but I feel the larger sheets present more wastage if you're working on curved areas plus it's about $3/sq.ft. I did the doors, floor, and tunnel on a friends Acura. Really took the buzz out and helped out his sound system.

I've done 2 Miatas now with the Polyken product and definitely prefer it. At just over $.50 /sq.ft it's hard to beat. I remove the plastic door liners and install pieces to clear all bolts and holes on the side facing the interior. The strips work out well because you don't waste as much. I then reinstall the plastic with shoe goo over the foiled tape. I also do the fire wall, wheel tubs, tunnel, and rear deck. A warning, this stuff bonds tenaciously so you have to consider the job permanent. Do not cover anything you'll later need for access. The difference is phenomenal on a Miata. It really helped reduce exhuast resonance and virtually eliminated all the buzzing associated with a light car. The aluminum facing reduced heat gain through the tunnel and seems to have made my component system sound much brighter. I have transducers in my seats that used to shake the floor pan on heavy bass tracks. The doors now have that nice Jag sound when you close them. I haven't done my Q yet but am sure it will benefit greatly. The 6x9's in the Q doors sound great but need some final tweaking for a perfect fit; I'll do the sound damping at the same time. I usually buy either the 6" wide roll unless I'm covering a lot of flat stuff and then buy the 12". There are other roofing tapes that are similar at Home Depot but either they are only 1/3 the thickness or are made from an unfaced bituminous material. The Polyken product is the only one I can vouch for and our local guys sells it as "Peel n' Stick" In a hot climate the bituminous products just plain stink up the inside of the car so I would avoid them. If you put the bituminous stuff on in the winter you don't notice it as much but wait until that 1st 100 deg. day when it sits in a parking lot, the stench is very bad! For me it all comes down to $$$, if I can get good results from an alternative product I go for it. Hope this helped.

Steve

[brucepelletier]

Bruce,I have tried the McMaster-Carr sheets (36"x40"x.062" thick, Part # 9709T21 @ $18.08/sheet) It works OK but I feel the larger sheets present more wastage if you're working on curved areas plus it's about $3/sq.ft. I did the doors, floor, and tunnel on a friends Acura. Really took the buzz out and helped out his sound system.

I've done 2 Miatas now with the Polyken product and definitely prefer it. At just over $.50 /sq.ft it's hard to beat. I remove the plastic door liners and install pieces to clear all bolts and holes on the side facing the interior. The strips work out well because you don't waste as much. I then reinstall the plastic with shoe goo over the foiled tape. I also do the fire wall, wheel tubs, tunnel, and rear deck. A warning, this stuff bonds tenaciously so you have to consider the job permanent. Do not cover anything you'll later need for access. The difference is phenomenal on a Miata. It really helped reduce exhuast resonance and virtually eliminated all the buzzing associated with a light car. The aluminum facing reduced heat gain through the tunnel and seems to have made my component system sound much brighter. I have transducers in my seats that used to shake the floor pan on heavy bass tracks. The doors now have that nice Jag sound when you close them. I haven't done my Q yet but am sure it will benefit greatly. The 6x9's in the Q doors sound great but need some final tweaking for a perfect fit; I'll do the sound damping at the same time. I usually buy either the 6" wide roll unless I'm covering a lot of flat stuff and then buy the 12". There are other roofing tapes that are similar at Home Depot but either they are only 1/3 the thickness or are made from an unfaced bituminous material. The Polyken product is the only one I can vouch for and our local guys sells it as "Peel n' Stick" In a hot climate the bituminous products just plain stink up the inside of the car so I would avoid them. If you put the bituminous stuff on in the winter you don't notice it as much but wait until that 1st 100 deg. day when it sits in a parking lot, the stench is very bad! For me it all comes down to $$$, if I can get good results from an alternative product I go for it. Hope this helped.

Steve

Yes, thanks. I did some digging and found out the following. The product is called Polyken Foilastic 35 mil. It's available in widths of 2", 4", 6", 9" and 12" by 50 foot lengths. I picked up a 2" roll this afternoon at a local San Francisco buidling supply yard. It doesn't seem to have the lead barrier layer that some of the other sound damping materials have, unless the shiny aluminum looking foil does the same thing? The 2' roll cost me $6 including tax which I think I calculated correctly as working out to $1.38 / square foot. It looks like it could work but I've never used any other sound damping product so I'm hoping for a little more hand holding by the experts.

[Highway Q45]

Thankfully the Polyken doesn't have a lead barrier. Even at a normal 1/64" (15 mils) thick that lead layer would weigh in at 1 pound/sq.ft. That's 10 sq. ft. per door (40 lbs); floors, tunnel, and wheel tubs (50 lbs plus)...it can add up quick. The lead core stuff probably has a better noise reduction coeffiecient (NRC) but I think you'll find the Polyken stuff works just fine. The Q already is leap years ahead of most cars in effective noise reduction. I think you can probably buy it cheaper in wider widths or if you know someone with a contractors license. I haven't used it yet on the Q but it worked out great on the two Miata's which aren't known for their quiet interiors. I think on a Q the best locations would be the doors, foot wells/wheel tubs, trunk divider, and tunnel area. The floors are already done pretty well anyway. The foil acts as a pretty efficient radiant barrier to reflect away heat so some benefit from a HVAC standpoint might also be realized. Give a door a try in a wider size roll, give it the "firm close" test, you'll see. If you want, I'll see if I can get it for less here in Sacramento where I buy it.

Steve

[maxnix]

Quote »Thankfully the Polyken doesn't have a lead barrier.[/quote] That is why soundcoat and others work so well in attenuating low frequencies, where most of the acoustic energy is.

There is very little effective sound isolation without adding mass for acoustic damping.

[bpmguys]

a question that i have to the people that are spraying undercoating inside the doors is, does it tend to seep out of the bottom during hot summer days. I have used the 3m product and a product that is produced by, if i remeber correctly, wurth usa. the wurth product was the better of the two. it was heavy and held up well over the years.

[diamondj30]

i had to use the undercoat to quite my door handles,made 3 tripts to cali over summer its still there .i did it 3 years ago.i use about 5 kinds of rubatex in the car too. i have 2 layers 3/4"apiece of rubo on all my outer door skins .moistior,spelling,oh well.heat barrier,non mildo.thats 1 1/2 inches.i can remove it for ding guy.tyook out headliner put visciolastic and 3/4"rubo in top.ecch door skin has 3 layers.8s in boxws in front doors no vibration,super little.i also have rubo on inside of doors too over visio.i used expanding foam alongroll bars in doors.whole florr visio,and now rubotex.no more blue stuff.you cant here my doors unlock.one layer on top car..ive never had any waste since there is some much to do.i did back deck with viscio and rubatex tape.8s in .33 airspace boxes secured to back deck,no noise at all there.all heat shields under car.varios linkages like for the trunk.trunk lid has v and real good caulking.5 layers on rear of car.both of my js leaked air from outside at the front of the doors.car got so quite i could here it.extra stripping on door next to dash got rid of it.dash and door stay clean now.its insane what you can doto make them quite,like a 40 k car should be.i also did gas tank and that entire area.hated to hear fuel pump.

[brucepelletier]

That is why soundcoat and others work so well in attenuating low frequencies, where most of the acoustic energy is.

There is very little effective sound isolation without adding mass for acoustic damping.

Can you tell us please exactly which Soundcoat products you used and how applied? Thanks.

[brucepelletier]

i had to use the undercoat to quite my door handles,made 3 tripts to cali over summer its still there .i did it 3 years ago.i use about 5 kinds of rubatex in the car too. i have 2 layers 3/4"apiece of rubo on all my outer door skins .moistior,spelling,oh well.heat barrier,non mildo.thats 1 1/2 inches.i can remove it for ding guy.tyook out headliner put visciolastic and 3/4"rubo in top.ecch door skin has 3 layers.8s in boxws in front doors no vibration,super little.i also have rubo on inside of doors too over visio.i used expanding foam alongroll bars in doors.whole florr visio,and now rubotex.no more blue stuff.you cant here my doors unlock.one layer on top car..ive never had any waste since there is some much to do.i did back deck with viscio and rubatex tape.8s in .33 airspace boxes secured to back deck,no noise at all there.all heat shields under car.varios linkages like for the trunk.trunk lid has v and real good caulking.5 layers on rear of car.both of my js leaked air from outside at the front of the doors.car got so quite i could here it.extra stripping on door next to dash got rid of it.dash and door stay clean now.its insane what you can doto make them quite,like a 40 k car should be.i also did gas tank and that entire area.hated to hear fuel pump.

Can you be more specific please about products you used? Brand names? Types? How applied?

I especially like your mention of being able to remove sound damping material on outer door skins to allow ding repair. This is a concern of mine in using a non-removeable material.

[diamondj30]

im so lucky i live near boeing,they use the rubatex.i buy all i can get my hands on.its there over stock short bundles ect.i havnt been able to find it anywhere else.go to home depot use your emagination.they have everything.you can get rubatex tape and duct wrap there,i also use it to.comes in rolls.i wash down all surfaces with acetone before application.visciolastic,use heat gun.rubo tape has adhesive back.personally i wouldnt put visciolastic on outer door skin,cannot take off easy enough.

[brucepelletier]

I just bought some Soundcoat GPDS (general purpose damping sheet) to use on the rear package shelf when I reinstall the refurbished Bose speakers this Saturday.

This stuff is not cheap - 9 square feet at $40 ($4.44 per square foot) - so I'm hoping it's worth it. I'm not using much but it adds up.

I just talked to the local sales rep in the SF Bay Area and he's kindly offered to spend some time next Saturday morning looking over the Q to recommend various Soundcoat materials to quiet the car.

[diamondj30]

cool

[natsoundup]

keep us posted....

[maxnix]

Quote »This stuff is not cheap - 9 square feet at $40 ($4.44 per square foot) - so I'm hoping it's worth it.[/quote] I think you will find their products are the best designed, not the cheapest.

Please take pictures so we can share your experience and your comments on the results.

[brucepelletier]

This past Saturday I reinstalled the speakers refurbished by Bose in my 90 Q (see Speaker Amps thread for more).

I installed 2 layers of Soundcoat GPDS material in both front doors. It's a great improvement. The doors now close with a thunk instead of a clank and the front speakers sound much more focused.

The GPDS is very easy to work with and although rather expensive you don't use much as there isn't that much free surface area on the outer door skins to cover. I covered the area below the outside rub strip on both sides of the original bituminus looking patch inside each door. And I also added large patch right next to each door handle.

I did not take photographs as it was a job in itself to get everything opened up, treated and the speakers reinstalled all around. But it was not a difficult job, just a little time consuming if you want to do it neatly.

The rear speakers are the more difficult to do. You have to remove the lower seat cushion entirely and pull the rear cushion forward and keep it out of the way with the shoulder belts still attached and pulling back the whole time. A lot of energy expended just keeping is out of the way. Then you have to pull out the package shelf. Whew! It was a good opportunity to really clean the rear window and brush and vacuum the rear package shelf. I even replaced both lamps in the high-mounted stop light when one of them blew out while reinstalling.

There is a lot of original thick black rubber-like damping sheeting all over the sheetmetal of the rear package shelf, rear seat back and rear seat cushion so I didn't add any Soundcoat there. I recommend this as a very do-able DIY project.

[LAQ]

a lot of info here.

so going back to spraying foam under the wheelwell, doesnt that look tacky? or am i missing the fact that this foam can be shaped or painted to make it look like it is part of the wheelwell?

[brucepelletier]

Last Saturday I went over sound damping the Q with the local Soundcoat sales representative. We concentrated on the easier to get to area of the trunk.

One idea is to apply a lead core sheet on the trunk separator/finisher panel, the one at the back between the gas tank and the trunk. For some reason this panel is open at the top about 1". Is there some function to this opening? Venting the gas tank area? Allowing the rear speakers to vent into the trunk area? Is there any reason NOT to seal this compartment off completely?

I'm also looking into a foam/damping layer sheet for the entire trunk floor. I want to go to a full-size spare and this will require building up the trunk floor to match the extra height over the compact spare. I'll loose some trunk depth but this could kill 2 birds with 1 stone. Is this an area that needs damping?

Also, will lay some of the lead sheeting over both rear wheel wells in the gas tank compartment. Just loosely pack it in so it can be removed for shock replacement.

Any benefit in damping the trunk lid, too? Has anyone done this?

Still trying to figure out how to damp the front wheel wells. Has anyone done this from the inside, in the front kick panels where the TCU and ECU live? I hear the most noise from this source.

[elwesso]

I have a question. My Q is very quiet (although i am used to a grand prix, so anything is quieter than that!) and there seems to be a lot of wind noise coming from the windows and the doors. What do you recommend using around the window seals and door seals? Is there anything else that i could do to make it quiter without taking apart too many things, if any at all??