Radio Speakers??

[floydv]

Before any goes crazy installing a mega-sound system in their Elio, your first consideration should be the acoustic environment. Remember this is designed from the outset to be an economy car - so it's not going to be hauling around a lot of expensive insulation. At present there seems to be NO insulation in the cabin, only a thin plastic shell between you and that noise-maker up front, and three tires droning away to either side and out back. You're going to start with a noisy little box, and no amount of kilobucks is going to overcome that. It's going to be LOUD in there. The fix is relatively cheap, but it is going to be fiddly.

I'd consider a complete insulation package as a first step - pull out any interior pieces you can, seats, any trim panels that you can safely remove, then trim and stick slabs of Dynamat everywhere you can reach, particularly to the firewall and floor - all the way back to cover the rear wheel housing. This MAY get you up to par with the cabin silence of most mid-line cars. Check any holes in the cabin and install close-fitting rubber bushings where wiring or mechanical linkages pass through the firewall and engine noise can enter. You may want to install a tach - after treating my boat in a similar manner, I found it was about the only way I could tell when the engine started.

Once you have most of the thrashy and rumbly bits silenced, your Elio may still have some sound leakage issues, particularly in the single-seals around the door, hatch, and lightweight windows. Luxury cars today often have triple door seals, even extra-thick windshields that positively seal the cabin from road noise. There's not much you can do with these, but by controlling most of the exterior noise from entering the cabin, you'll have a huge head start on building an entertainment system that will justify its expense.

Some caveats for you all to consider. When the smart came to the US in 2008, a number of owners immediately set out to improve the acoustics by applying Dynamat and other sound deadening materials. In several cases, applying the Dynamat directly to the inside surface of the plastic body panels resulted in very noticeable warping in situations where the car was subject to warm climates.

I posted my theory at that time which seemed to explain the phenomena:

According to this article, plastic door panels have a high linear coefficient of expansion (relative to steel) and must be able to expand in two directions:

Quote:
Expansion and Contraction. Plastics suppliers have had less success in overcoming another traditional problem–the pronounced expansion and contraction plastic panels undergo during temperature extremes. Plastics have a much higher coefficient of linear thermal expansion (CLTE) than steel, and therefore require more space to grow and shrink. This leads to wider panel gaps than most automakers, driven by quality survey results to eliminate fit-and-finish concerns, are comfortable with. The problem can be ameliorated on fenders and side panels by firmly securing them where they meet the door and allowing them to expand in only one direction. But that doesn't work with doors, since they have to be free to expand in two directions. Plastics CLTE has been reduced in the newest formulations by tweaking blends and adding mineral fillers, but it is still nowhere close to steel and no one really expects it to get there. GE Advanced Materials' Aoki says that gaps can be successfully managed through clever design, and he points to his company's extensive design work on smart's plastic-paneled lineup as proof. But like Saturn, smart's vehicles are designed from the beginning for plastic use, and it's unlikely that automakers will be willing to upend their design processes in order to accommodate the vagaries of polymer doors. Indeed, fenders and side panels are seen as a growth market for plastics precisely because special handling has been eliminated.Feature Article - Sensors Make Sense - 06/04

So perhaps what's happening is that your use of foil-backed and non-foil-backed Dynamat creates enough of a thermal gradient in your door panels while they are sitting in the sun to cause the denting. Because the plastic has to expand in two directions, and the temperature gradient creates two different regions of thermal expansion, the end result is the puckering or dents that you're seeing. Just a theory.

I recall some smartcar forum members recommended the use of the foil-backed Dynamat, rather than the non-foil Dynamat, to avoid this situation when applying the material to the inside surface of a plastic body panel. The recommendation also said to make sure you cover the entire inner surface of the panel to avoid creating pockets of thermal gradients. I'm not sure if that was a successful approach although the basis for it seemed sound. FWIW and YMMV.

 

[Coss]

Maybe not, but I think it's only a matter of weeks after the Elio is released that someone makes a 3rd-party version of the "Rocker Pro" to swap out for the standard Elio seat. IF nothing else, you need to put the audio controls in the armrests like the captain's chair in Star Trek.

As for the Dynamat solution, I'd welcome someone selling a kit of pre-cut Dynamat material along with step-by-step instructions to allow the minimally-mechanical among us to apply the material, or pay someone to apply it for us.

It's not that hard; it's a big sheet of tar paper that's very expensive and you just cut to size, peel and stick.

 

[Coss]

Some caveats for you all to consider. When the smart came to the US in 2008, a number of owners immediately set out to improve the acoustics by applying Dynamat and other sound deadening materials. In several cases, applying the Dynamat directly to the inside surface of the plastic body panels resulted in very noticeable warping in situations where the car was subject to warm climates.

I posted my theory at that time which seemed to explain the phenomena:


I recall some smartcar forum members recommended the use of the foil-backed Dynamat, rather than the non-foil Dynamat, to avoid this situation when applying the material to the inside surface of a plastic body panel. The recommendation also said to make sure you cover the entire inner surface of the panel to avoid creating pockets of thermal gradients. I'm not sure if that was a successful approach although the basis for it seemed sound. FWIW and YMMV.

One thing about sound proofing; on something like a door, you don't need to cover the whole inside of the outer panels; you're trying to dampen sound.
A large piece that covers about 30% of the inside of the door skin is enough. Where you need full coverage is on the backside of the door panel.
Full floor, wheel wells and firewall; also behind the headliner to keep the roof from resonate sound (aka kill vibrations) so a couple of squares behind the headliner, against the roof skin is all you need.
Then under the carpet, up the firewall, and the rear seat area, you use a heavy jute padding. It's a combination of the dynamat and the jute that will give you a quiet interior.

 

[WilliamH]

It's not that hard; it's a big sheet of tar paper that's very expensive and you just cut to size, peel and stick.

Before we all go crazy with this, I remember reading in one of the Elio blogs that they didn't put insulation in P5 to facilitate installing and removing body panels. Could someone ask the tour team if this is still the case?

 

[Coss]

Before we all go crazy with this, I remember reading in one of the Elio blogs that they didn't put insulation in P5 to facilitate installing and removing body panels. Could someone ask the tour team if this is still the case?

I really doubt that they would roll it out the door with no insulation; it will have some, but not Rolls Royce grade sound deadening.
Probably more like Chevette grade.

 

[slinches]

I honestly don't know what the best approach for sound deadening will be for the Elio. In traditional vehicles, body panels are metal and are integral to the frame so adding damping is highly effective. With the Elio's tube frame and non-structural panels, it may be better to isolate the frame structure from the panels to eliminate structure borne noise and then use some open cell foam and lighter weight mats to absorb the airborne noise. Also, the SMC panels should have some decent damping on their own, so the aluminum backed butyl rubber mats may not be that effective.

 

[WilliamH]

I really doubt that they would roll it out the door with no insulation; it will have some, but not Rolls Royce grade sound deadening.
Probably more like Chevette grade.

Just for clarity, when I said "P5" I specifically referred to the Red prototype vehicle, not E versions or subsequent production versions. We should also keep in mind that it was reported that the body panels on the P5 are fiberglass and not the SMC panels that are planed for production.

 

[ehwatt]

I really doubt that they would roll it out the door with no insulation; it will have some, but not Rolls Royce grade sound deadening.
Probably more like Chevette grade.

Man, if it's got ANY it'll have a lot more than my chevette (bless it's little heart).

 

[Coss]

Man, if it's got ANY it'll have a lot more than my chevette (bless it's little heart).

I loved my 76 3dr 4 speed Chevette; I drove the doors off of it, and it kept coming back for more.
And it had insulation, not much, but some

 

[Trusting]

At $6,800 I expect it to come with 2 weenie speakers.

I seem to remember that years ago people used to have "undercoating" applied to their cars. This prevented rust and was also said to reduce road noise.