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I measured 87 db at ear height on the highway. That's with a hard top and the behind seat foam. I have aftermarket exhaust, but I can't hear it over the wind noise.
 

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This is great info...

before my Elise moved away from a street car into a track car, I had a dynamat layer on the firewall and that alone made the car so much more liveable.
 

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I feel the wind noise with the hard top off makes the car seem less loud. It drowns out the engine and exhaust noise. With the hard top on the engine noise and exhaust is more pronounced.....not sure which is really louder though.
 

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Same car

I find this interesting.

I have the same car as you, a 2009 Saffron Yellow Elise Purist Edition.

With either the softtop or hardtop in place I find the noise level is both fun and fine.

I am running the stock muffler and I have the normal Elise carpets.

In the summer without either top on, the noise level rises significantly.

I've never found the desire to have the noise level be less and I'm a daily driver.

I guess I've been driving an older car for more than 20 years and have gotten attached to noisy rides.
 

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Discussion Starter #26
I find this interesting.

I have the same car as you, a 2009 Saffron Yellow Elise Purist Edition.

With either the softtop or hardtop in place I find the noise level is both fun and fine.

I am running the stock muffler and I have the normal Elise carpets.

In the summer without either top on, the noise level rises significantly.

I've never found the desire to have the noise level be less and I'm a daily driver.

I guess I've been driving an older car for more than 20 years and have gotten attached to noisy rides.
Understandable. Then I would not recommend this mod for you. If the noise level is not loud enough to your liking you could drill some holes in the firewall to let more through.

Seriously people. No one is holding a gun to your head. It's only for those who are wanting a quieter ride. If u want a louder ride I'm not going to criticize that. Your car, your choice.

And for those actually interested in this mod, the wife and I took it out today, and she was thrilled that we could actually have a conversation without having to yell. WAF +10.
 

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Nice write-up. Installing a hardtop though will make a very noticeable reduction in the cabin noise. I find that with the hardtop on and ForcedFed exhaust system (not as loud as the Arqay or Lotus sport exhausts but louder than stock), the noise is very tolerable as a sports car. With the softtop on, typically my ears start to feel it after an hour of driving.
 

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So does your car not have carpeting over the firewall nor the floor? Or are you mounting this under the "carpet"?

IMO the stock Elise is too noisy. If I can't hear my passenger, or I come home with ringing ears, that's not good. You only get one set of ears in this lifetime.

I installed this stuff on my race car after suffering hearing issues from exhaust noise. It was really important to reduce the resonance in what was originally the rear passenger compartment and trunk.

Other sources of this are Aircraft Spruce (aircraftspruce.com) which has a nice write-up on installation in aircraft and cars. Also, the industrial supply house McMaster-Carr has sound insulation.
 

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soft top quieter than hard?

when i bought my 06 elise( stock exhaust) i was "sure" the hard top was both better looking and quieter. then an ex-lotus engineer told me the soft top was quieter by several dB. Since then i have tried both and think he is right. the hard top seems to reflect the noise back inside while the soft top absorbs it. maybe someone could take measurements of both to sort this out.
 

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Clarification

No one is holding a gun to your head. It's only for those who are wanting a quieter ride.
My post about noise levels on a stock Elise being "fine" was not meant to say I'm critical of your choice to make the ride quieter.

I just sort of thought (wrongly) that everyone was happy with the noise level of an Elise with a stock setup.

I'm now interested to see how many people want to make it quieter.

I also noticed that your Elise didn't have carpets, but mine did. How much effect does that make on noise levels?
 

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Discussion Starter #32
I honestly don't know how much of a difference carpets make, I guess it depends on their design, I've never seen any carpets except the mats. But based on everything I have read probably not much difference. Foam alone does not attenuate sound very efficiently, you need it coupled with some sort of mass barrier, and vinyl appears to be the substrate of choice in most circles. Carpet is light so it cannot act like a mass barrier, and does not have construction like a decoupler (typically foam type product) so it would not act as a decoupler or even insulator really.

Also there is no vibrational dampening with the carpets. The only place I have seen vibration dampening is on the floor under your feet, at least in my car not sure it has always been there. That is what that black pad is, it is not for noise insulation but vibration dampening.

Sorry about if my last reply was harsh. It is a common expressed opinion based on my reading here that both the noise level and degree of low frequency noise (drone) is considered excessive by a large number of people who own and operate these cars, including me. I honestly don't care how loud people choose to have their cars, I just dont want my car loud, and I took you post to say that there was something wrong with someone for wanting a quieter ride.

But, it's all good, I know we'll both love and enjoy our elise's, I'll just be enjoying the radio while you are enjoying your engine growl, nothing wrong with that
 

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Discussion Starter #33
Looking around the car for large panels that would rattle/resonate, and I decided to address the under engine access panel (sorry, don't know the official name).

Basically I pulled the panel, cut a strip of damplifier around the air scoops, and put it back up in place. Added weight about 0.5 lb approximately.

To cutout around the air scoops, I traced one scoop on paper, then after deciding where "center" was by laying the damplifier over the panel, the scoop pattern was traced from the paper onto the damplifier with a pen; the damplifier has an aluminum back layer that will score very easily so writing through the paper makes a very noticable mark. Then just cut out the tracing. After the first scoop (left most) was cutout, I laid the damplifier over the panel, and positioned my paper tracing over the second air intake, then holding the paper in place over the damplifier moved them to a flat surface and traced the second scoop, then cut...The process was then repeated for the 3rd scoop.

The most noticeable improvement is in the road noise, especially the rattly noises on rougher roads and when hitting bumps etc...Now there is virtually zero of that rattle like your riding around in a aluminum can (which I guess we really are), and now it feels and sounds solid...very solid...It's hard to explain exactly but it definitely took away that "cheap" feel to the car that it use to have from hitting even tiny bumps. Rougher roads seem much less rough than before, simply because you barely hear the roughness of the road compared to before.

See picture below. I'm still searching and plan to make the elise as comfortable (e.g. solid and quiet) of a ride as possible. Next up....doors...
 

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I find the noise only becomes tiresome on long highway jaunts. You don't always have to tach it out during city drives. :cool:
 

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Great to know! First time I went over those silly little markers on the freeway I really cringed... I'm taking Friday off to install the new audio system and do your earlier cabin mods (the Elise is now my daily driver). I'll tack this on the list, too...
 

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Discussion Starter #36
Zuspiel, one tip when you are putting down the Damplifier, only peel and fold back an inch or two of the backing, then position carefully and press the sticky edge down. You can then carefully peal back the backing as you work from the stuck edge down and press into place. It is quite sticky, and dealing with a large sticky surface makes it much harder to get it positioned just right.
 

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Thanks! That makes sense. Mine is still somewhere on a UPS truck but from the description, it seemed to be a "stick down exactly once" kind of thing... ;)
 

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I've spent quite a bit of time on this, in various configurations--I wasn't so much focused on making it quiet, but more of the good sounds and less of the bad. Also so I could put a lighter (and louder) exhaust on and not wear ear plugs.

What I found is that you can make the car really quiet. Eerily quiet. I found I didn't like it. The wind noise suddenly dominates and you can't hear the tasty interaction of the tires with the road at all.

I also cut removable sound barrier for all floor panels, and put sound barrier in front of firewall, and found those were definitely not worth the weight.

As for the exhaust noise, in a nutshell, I found adding sound damping and barrier to be a losing battle with an exhaust. You have to hang weight all over the passenger compartment just to quiet the exhaust. I then made a custom aluminum deflector with sound barrier lining, sitting right behind a side-exit exhaust to absorb and deflect sound coming toward the cockpit, to quiet it a bit at the source. It was barely noticeable.

So then I gave up and just went back to the stock exhaust. There was just no way (short of adding 50lbs) to keep a loud exhaust from penetrating the cockpit.

As for sound quality, I found
- damping sheet beneath seats (if not already there)
- no touring pack firewall foam (doesn't make much difference if you have damping sheet, and since touring foam weighs 5 lbs, it's better just to put some damping sheet there and get away with less weight)
- damping sheet on firewall itself
- just a couple squares of damping sheet on the plastic firewall cover (I originally covered all of it and removed most and it made little difference)
- small damping sheet and tiny bit of sound barrier in door skins
- a couple pieces of sound barrier inside body near intake if you have the cup box

... made for a much more pleasing, classy sound. Really awesome. Less road noise, but not insulated and weird, either. I think the total is now 7 pounds added, and the sound sounds tuned, not just noisy. BTW, this made the stock exhaust sound a lot better too. In part by muting some of the intake noise so you didn't get that sudden blare at WOT. I don't wear ear plugs even for long drives and I'm on A048s.

All in all, the weight adds up really fast, and I found just a tiny bit in the right places was all that we needed.

Can post some pics if it's interesting.
 

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Discussion Starter #39
I'd love to see pictures. I'm always interested to see other peoples approach, and poach whatever seems to work.

I think your point is very astute, a significant gain I have found in addition to a general decrease in the "volume" of noise is that the quality of the noise is significantly improved. At high RPM you can still hear the engine scream, but the quality of the noise is more satisfying and not aggravating like it was before. At typical cruising RPM's (3000-4500) I have a nice hum in the background but the drone is largely eliminated.

My goal is not to make it silent, but to make the sound a bonus not a distraction to the experience.....at least to the experience that i am wanting...

I know that I could make the car very quiet, but as you pointed out the weight gain would be very large, I think probably 50-90 lbs depending on how quiet you really wanted. But, what I am really aiming for is noise and vibration control with as little weight gain as possible....Aiming for 15# or under.
 

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Would sound barrier or damping in the trunk help? It's like a resonator box right above the exhaust. I've got the removable carpet but maybe there's something more effective.
 
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