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Sound Damping To Reduce Tyre/road Noise.


Rapidone
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I've been looking at some of the sound deadening products that adhear to the floor of the car, under the carpets.

Have any of you tried doing this or had it done for you? Or have tried any other kind of sollution?

Are the carpets easy to get in and out?

I noticed this review of the process, but it looks like a big job.

http://www.hometheaterhifi.com/volume_10_2...ing-6-2003.html

Thx.

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I did quite of work on my previous car (an MG ZS180) because it had almost no soundproofing due to cost cutting.

Under the carpets I put an underlay made up of a thick fibrous material with a rubber crumb, which helped quite a bit. I also lined the insides of the doors with dynamat, which reduced noise and improved the quality of the sound system.

I'm really surprised your car needs it though, the IS is supposed to be a very quiet car, my old-shape one is. Are your tyres getting worn because they can get noisy. Try changing them and possibly look for a different make.

Some degree of road noise is unavoidable especially on low profile tyres. It also helps give you a sensation of speed which is not a bad thing :)

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I used these guys about 6 years ago and the stuff was pretty good! They are only in Oldham too! :)

http://www.noisekiller.co.uk/

I found them on a web search earlier and have already sent them and email, they're only a couple of miles from where I work, which would be convenient.

It's interesting to know they've been around for 6 years at least.

I'll see what they can offer on prices. I dont like the idea of doing the job myself, but if the price is too high I may have to.

As for the noise levels in the IS250, the engine is almost silent when warmed up, and there is very little wind noise. However I'm having a little problem with the road/tyre noise.

Probably the tyre noise is more noticable than in other cars, because of the lack of engine and wind noise, and I think I'm proabably more sensitive to noise than most people aswell.

The PC I'm using to type this is barely audible, with slow, low noise fans and a sound insulated case. A standard PC drives me nuts, like a vacuum cleaner running constantly.

The coustom job that I linked to had oustanding results, an 8db drop. What's that? 70 to 80% less noise. That's a huge reduction.

Considering the price of a new IS250, I'm very surprised that this isn't done from new. Would proabably add only a couple of hundred pounds the the list price. It would have made sense putting in a less exensive sound system and doing the sound proofing instead.

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Considering the price of a new IS250, I'm very surprised that this isn't done from new. Would proabably add only a couple of hundred pounds the the list price. It would have made sense putting in a less exensive sound system and doing the sound proofing instead.

There will definitely be sound proofing in the car already, but they use it sparingly because it adds weight and costs money.

You should try driving a car without any soundproofing, like the MG I mentioned. Then you'd think the Lexus was well soundproofed!

I am curious about the new IS though, would be good to get a go in one to compare to my IS200 but I'd have thought the IS250 would be quieter than the IS200 to be honest.

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They've probably got to be careful with stuff like this as if they were to noiseproof it too much - as stupid as it sounds - you just know someone's going to sue Lexus at some point when they have an accident as "they didn't hear it coming"!

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The coustom job that I linked to had oustanding results, an 8db drop. What's that? 70 to 80% less noise. That's a huge reduction.

Sorry but 8dB is only a reduction of 57%, and because of the way the ear works, 50% reduction is only just noticeable. Measurements with a sound level meter mainly show the reduction of relatively high frequency sound and will largely ignore the low frequency of road rumble because their characteristics are designed to fit around the roughly the frequency range of the human voice - I could bang on about weighting curves, but what I put earlier is the gist. This means that the 8dB reduction is mainly in almost everything other than road/tyre noise.

If you really want to reduce road noise, it will make your car look naff - fit steel wheels with supple high-profile tyres. If alloys weighed less, they would help handling, but they generally aren't and are mainly cosmetic with a rigid construction which transmits more noise from the roads. Similarly, so do low profile tyres, and for the driver who doesn't push his car towards the limits, contribute nothing but noise and a cool appearance. If you get a chance, try an old quality car with steel wheels and tall tyres, and you will be amazed how road/tyre noise just isn't there.

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If you really want to reduce road noise, it will make your car look naff - fit steel wheels with supple high-profile tyres. If alloys weighed less, they would help handling, but they generally aren't and are mainly cosmetic with a rigid construction which transmits more noise from the roads. Similarly, so do low profile tyres, and for the driver who doesn't push his car towards the limits, contribute nothing but noise and a cool appearance. If you get a chance, try an old quality car with steel wheels and tall tyres, and you will be amazed how road/tyre noise just isn't there.

Yes that's true, I once compared my dad's Rover 45 against my MG ZS. Essentially the same bodyshell, but one has 15" rims with chunky tyres, the other has 17" rims with 45 profile tyres. The difference is massive, you'd think the doors were missing in the MG it was that noisy.

Your point on alloys transmitting noise is interesting, I once wondered if it was possible to apply dynamat-type material to the outside rim of the wheel (hidden by the tyre). It sounds a bit daft and obviously you'd have to do it in a way that would avoid problems balancing the wheel, but the question is - would it make a difference?

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I have 2 fully covering layers of Dynamat in both front dorrs with other overlaying patches around

the speakers themselves, 3 layers on the bootlid etc and 2 layers under the rear seat bench/seat back.

It makes a big difference as people who have been in my car have noticed compared to their IS200's.

DynamatDoorSkin.jpg

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Which tyres are you using.?

Dunlop SportMaxx. The only review I've seen on the effect of different tyres on noise, showed a 3db difference from worse to best.

Sorry but 8dB is only a reduction of 57%, and because of the way the ear works, 50% reduction is only just noticeable. Measurements with a sound level meter mainly show the reduction of relatively high frequency sound and will largely ignore the low frequency of road rumble because their characteristics are designed to fit around the roughly the frequency range of the human voice - I could bang on about weighting curves, but what I put earlier is the gist. This means that the 8dB reduction is mainly in almost everything other than road/tyre noise.

If you really want to reduce road noise, it will make your car look naff - fit steel wheels with supple high-profile tyres. If alloys weighed less, they would help handling, but they generally aren't and are mainly cosmetic with a rigid construction which transmits more noise from the roads. Similarly, so do low profile tyres, and for the driver who doesn't push his car towards the limits, contribute nothing but noise and a cool appearance. If you get a chance, try an old quality car with steel wheels and tall tyres, and you will be amazed how road/tyre noise just isn't there.

Well, the note of the noise I get, is simmilar to the sound you get if you put a sea shell to your ear. I don't hear much low note rumble.

As for the wheel size, that's always an option. A friend of mine put some big alloys and low profile tyres on his focus, and the car was alot more noisey after the change.

It would be nice to try some different wheels and tyres, to see if there was much difference in noise. I wonder if the local Lexus dealer would lend a set of 16" wheels and tyres off a standard IS250? I doubt it.

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Well, I was thinking of getting soundproofing for the boot of the car only first, since there seems to be so little in there already. So today I tried stuffing the boot full of bedding quilts to try and dampen the noise. I couldn't decern any change in noise levels at all.

I realy don't understand where the noise is coming from. Transmitted through the wheels up the suspension, or comming off the wheels through the air and into the the car throught the arches and floor.

If I knew which set of tyres to change to I would try a tyre change. I've keep reading and reading, but cant find anything conclusive.

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The quilts in the boot trick is an interesting idea, but it proves out that the noise you're heading is almost entirely down to ringing in the metal panels, caused by vibrations from the road. That's why wadding-type sound proofing doesn't work.

It's going to need full body-panel deading (i.e. dynamat) if you really want to kill noise. Or smaller wheels :)

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Yea, I think you are probably correct.

I've done alot of reading about tyres over the last week, and a set of 16" 225 wheels with 50 profile tyres seems like the best bet for lower noise.

I've also been looking at new tyres, Yokohama AVS dB V550 seem to be the best option for low noise.

Alternately just replace the tyres on the 17" wheels that are on the car, with the Yoko tyres.

The problem with this being, although the Yokohama 245/45 17 tyres for the rear wheels are listed on the manutacurers web site, they don't seem to be on sale in the UK.

There doesn't seem to be a problem with the 225/45 17 for the front wheels, they are fairly easy to find.

I'm unsure what to look at next, maybe a full set of 16" 225 wheels with 225/50 tyres, however I don't know the offsets of wheels to look for.

And don't know if there will be any handling problems running the same size tyres on both front and back.

This could take a while.

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  • 2 months later...

RApidone: I had the AVS db v550 on my is200 and i can tell you that it didnt reduce road noise much.. let me explain this:

The rolling noise of this tyre is lower than average, but the sound you hear in a car is transfered by the panels. and the avs db have hard sidewall which results in more vibration of the panels in your car > more noise inside thecabin. (the rolling noise outside is less)

back to topic: i added some sound damping material in my is200 and reduced noise with 6db ( measured by db meter)

What did i do:

1. i added this material http://www.noisecontrol.nl/resizer/resize...._achterkant.JPG on almost every reachable body panel on the is200 like: hood, doors, trunk, spare wheel well, rear wheel well, rearseat(gastank), the whole floor. only covering 80% of the body panel is enough. ITs heavy **** i have added +/- 60 kg of material.

This material stops the vibration alot for road noise ( for low freq noise)

2. i added this material http://www.caraudio-versand.de/shopimg/112067.jpg above the other one this material is very light and also used in carpet of different kind of cars. (for higher freq noise)

With both material the sound volume reached (75mph @63/64 db) as silent as a mercedes E class.

The other noise was coming from the wind.

This type of insulation still need to done on my is250, but i am too lazy :) hahahaha might do this when its less cold outside :D

I would suggest to do the floor, there is where the most road noise is coming from. I think you could reach at least 3 db with only doing the floor.

And every 3db is doubleing of the sound by a human ear.

Alan

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I am curious about the new IS though, would be good to get a go in one to compare to my IS200 but I'd have thought the IS250 would be quieter than the IS200 to be honest.

no question the IS250 is quieter over the IS200 however there is noticeable road noise. Much more so than a GS or even RX.

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I am curious about the new IS though, would be good to get a go in one to compare to my IS200 but I'd have thought the IS250 would be quieter than the IS200 to be honest.

no question the IS250 is quieter over the IS200 however there is noticeable road noise. Much more so than a GS or even RX.

After having my 08 is250 for a big whole week i thought there was a lot of tyre noise but im convinced the car is so quiet its the only thing i can hear!

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  • 1 year later...

sound deadening can be done on the is250. I have done this by different kinds of materials for sound deadening/insulation. I have reduced the interior noise by an average of 6db. every 3db reduction is comparable to half of the sound. So the noise level has been reduced 4 times of the stock is250.

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