Matting for road noise insulation

[Mless5]

What areas benefit the most in 325ix coupe and how many layers should I put on? I am in on the budget. Just looking for overall improvement, I understand that e30s are not meant for any serious setups.

Also, should I throw some on the rear firewall thus isolate the trunk from the cabin?

Thanks.

[StereoInstaller1]

If you want to do a significant reduction in road noise, do this:

Dynamat "Extreme" (or equivalent) covering the rear wheel wells, 2 layers.

A few strips (10" X 30") under the rear seat, too.

Cover the ENTIRE floor (from way up under the dash to the rear deck, completely) in "The Insulator", should take about 3 yards, shiny side up...then re-install your carpet.

You should see about an 8 to 10db drop in general noise.

Wind noise will not be affected. Nothing short of removing your rain gutters will change that.

Luke

[e34john]

How much would all that sound deadening weight Luke?

[Mless5]

I was kind of shooting for RAAMAT. Your thoughts on this Luke?

Thanks.

[StereoInstaller1]

I was kind of shooting for RAAMAT. Your thoughts on this Luke?

Thanks.

RAAMMAT is the same bullshit as any other butyl-based product...same bullshit "you need to cover every inch of the inside of your car with 5 layers of our product!" as anyone else.

I just love how these guys tell everyone that the corners make the biggest difference...tell me this: where is a panel going to resonate most, in the corners or in the center? Fucking DUH, huh?

A few strips in the center does 99.99% as much good in damping noise as covering the entire panel. That is why I recommend 2 layers inside the wheel wells ONLY: try and stop the noise where it starts. The resonance is primarily from the tires contacting the road.

Lets get one thing straight right now: these products do a piss poor job at reducing "road noise". These products stop metal from ringing...that is ALL they do. An actual reduction of "road noise" would have to focus primarily on aerodynamics...then get into heavy damping, like Caddilac and such, pouring gallons of thick goo into the chassis, filling the frame rails with goo...all kinds of shit. What I am talking about is the idea of "bang for the pound and buck" kind of deal...best performance, least weight.

Ya wanna try a neat little trick? Go get yourself some of the wide blue making tape. Go for a quick drive, windows up, paying attention to the wind noise. Pull over and tape your rain gutters so that the are 100% covered, trying to pay attention to the airflow...go drive the same route again and see the difference. In my old '77 Nova, it was stunning, at least a 10db difference. In an E30, it won't be quite so dramatic, but I would expect at least 3db.

So yeah, if you are covering the entire floor of your car, have fun. If you want it quieter, do strips and use "The Insulator". You will be blown away.

How much would all that sound deadening weight Luke?

Maybe 15 pounds...less than the excess flab around my midsection!

Luke

[e34john]

Maybe 15 pounds...less than the excess flab around my midsection!

Luke

I bet it helps keep the weight distributed with the stereo equipment you got in the back.

[m3_eater]

Forgive the resurrection of an old thread, but this looks like the best place to ask:

I'm pulling the E30 seats next weekend (sports going in), as well as installing a new head unit, running wiring to trunk for sub/amp, and new door pulls/map pockets. Obviously, this makes for a great time to install acoustic vibration dampening product throughout. I'm thinking of springing for Dynamat Xtreme instead of taking a chance on a lesser product - I don't want to do this twice. I want quiet and I'm willing to pay the price - both in weight penalty and for a quality product.

Questions:
1. I'm getting a LOT of noise from the transmission tunnel through the shifter hole, not in the least because of the E36 exhaust and an E46 6-speed (Getrags are noisy and the tranny extends farther back than a 260 or ZF!). Can I expect significant improvement from focusing Dynamat around this area?
2. Will a 7mil product fit everywhere under the carpet, including transmission/driveshaft tunnel?
3. How many layers thick on the trans/driveshaft tunnel area before reinstall of carpet will be a PITA or just look bad?
4. Is Dynaspray useful at all to get tight areas? Notice how their spec for it says acoustic loss factor is "available on request" instead of published like their other products.
5. My car is a four door. Any special info regarding making it quiet, other than door insulation for the extra doors?


This following is mostly for Luke: If I buy & install an Infinity Basslink firing through the (open) ski pass-through, will it provide decent bass to counterpoint MB Quart components (front and back) run on 60Wx4 peak Alpine head unit power? Should I instead Dynamat the entire trunk and experiment with firing the sub in another direction back there? My preferred bass sound is that of a sealed enclosure, BTW.

Thanks for any info & experience anyone can offer!

[Mless5]

This following is mostly for Luke: If I buy & install an Infinity Basslink firing through the (open) ski pass-through, will it provide decent bass to counterpoint MB Quart components (front and back) run on 60Wx4 peak Alpine head unit power? Should I instead Dynamat the entire trunk and experiment with firing the sub in another direction back there? My preferred bass sound is that of a sealed enclosure, BTW.

Thanks for any info & experience anyone can offer!

Get a real subwoofer and an amp. I can get you a good deal. PM me if you want more info.

[m3_eater]

Get a real subwoofer and an amp. I can get you a good deal. PM me if you want more info.

I used to be a big car stereo guy. In my last E30 I was running Boston Acoustics Pro Series 6.5s in custom door enclosures and rear shelf (5.4s), and two Kicker Competition Series 12" subs in (separately sealed) in a box in the trunk, with all PPI Art Series amps, Escoteric lines, 2 gauge main with a big fuse, distribution block, etc. I even had a sound processor that allowed me to adjust crossover points and gains throughout the entire frequency range, all from the front seats. Problem is, that stuff was HEAVY. All of this is to say that I want to get away from the weight.

Yeah, yeah I know - you need to move air to get bass - but I don't need the kind of bass I needed when I was young. I'll PM you regardless...

Anyone want to weigh in on the sound/vibration dampening?

[Mless5]

I heard (haven't tried) that Luxury Liner mat is the stuff to get to kill road noise. Might want to look into that.
As far as weight goes, I just sold a tiny Soundstream that pushed a single 10
no problem. The thing was size of an average book. Use Trupan instead of MDF in your enclosure to shave some more weight and you are getting there...

[808BMW]

2nd on the luxury liner, also the other stuff at

http://www.secondskinaudio.com/

Also try checking out http://www.sounddeadenershowdown.com