Sound isolation

[wavepower]

Awesome, informative thread Rasmus. All I need now is the car and the materials!

Anyone sourced the materials in the UK yet? Googled "vibroplast" and got this tread and non-English language sites. Is there a UK alternative?

[Rasmus]

You should search under accessories for car audio. Its possible, that Vibroplast or BiMast as such aren't sold in the UK, but you can use some other alternatives:
http://www.caraudiocentre.co.uk/cate...0&category=517
http://www.caraudiodirect.co.uk/acce...g-c-73_72.html
<there's plenty of materials there, go experiment!

[Rasmus]

Right. As most Civic owners I wasn't too happy with the sound of the original speakers, so after giving it some thought I deciced to change the front speakers.
I took time choosing the speakers - I didn't want to spend a fortune on them but yet they needed to be good quality, with a wide band and good output characteristics - to ensure nice, clean sound.
Since my car is a 1.8 Comfort - it only has 4 speakers (no tweeters in front), so I decided to go for coaxial speakers.
The speakers I bought in the end were MDS (a swedish company), model F216:
RMS rating: 100w, Max 200w, frequency 28 - 25000Hz, sensitivity 93,9dB.
Here is the best part - the price was only 38 euros for the pair (12 off).
Comparing them to the original speaker, we can see how pathetic the originals are:



As a tip from Pottsy's thread I also bought a set of Astra speaker adapters for 12 euros.
Then I removed the front door panels again, removed the old speaker, attached the rings, brazed the wiring and screwed the speaker onto the rings.

The thing that annoyed me the most was that the wiring - how on earth do you tell which is + or -??? If you wire the speakers up wrong, there isnt much use of installing better speakers - it will sound crap. So i had to try them out one way and the other until one wise guy came around and helped me out. I got so confused for a while, I'd probably still be in the garage if I was alone!
Anyhow, the speakers are, ofcourse, a lot better than the original ones. Before I didn't dare turn the volume past 25 - it sounded as if the speakers were about to rip. Now I can go all the way up to 35, it sounds loud and clear. The stereo now outputs sounds I never heard with the original speakers.
However, as clear and loud it may be this setup is still weak - there isn't enough bass. So I am going to have to install a subwoofer sometime soon.
I was thinking of going for an acitive woofer but a woofer needs RCA signal - so I'm going to have to remove the rear door panel to get the signal. Which means I really should install some new speakers there as well.
Meanwhile, the cops have decided to stop my drivinglicense for 2 months - so I guess there is no point in installing all this now if I can't use it

[WavyD]

Originally Posted by Rasmus

The thing that annoyed me the most was that the wiring - how on earth do you tell which is + or -??? If you wire the speakers up wrong, there isnt much use of installing better speakers - it will sound crap.

The easiest and most low-tech way to check, is using a 9Volt battery (you know the type with the contacts both at the same end). Hold the old speaker in one hand (with your hand on the cone) and touch the battery contacts onto the electrical contacts of the speaker. When the Cone Moves out, the contact with the battery positive on is the positive contact of the speaker. If you mark one of the wires and the contact it came off, you now know what wire does what.

[IronSoil]

Now I have also done the sound isolation to my car.

It was done by a car stereo installer here in Finland.

He used about 4 packages of Vibroplast, about 2 square metres of 4 mm bitum isolation and about the same with 2 mm bitum, other than Vibroplast.

On the doors he used Noxydol on the thicker parts.

He said that the weight of the car increased with about 50 kilos.

He isolated all the doors, floor and the whole trunk.

I have to say that it didn't help almost nothing to the road noise

So is there anything else to do?

Only thing left to do is to change the tires?

Now I have Michelin Primacy, 225/45/17.

Can I change to 205/50(55)17 or should I change the wheels too and buy 16 inch wheels+tires instead?

What brand of tires could be the most silent ones and would still be good tires?

Or is there something wrong with the sound isolation of my car? Shouldn't the sound isolation made make some kind of difference in the road noise?

[Rasmus]

Did he do the front footwells and rear wheelarches?
Doing the doors, trunk and only floor will not eliminate road noise too well, most of the noise comes from the tyres - so the area around them needs to be covered.
But then again, doing a complete sound isolation on the car will make it quieter, but you will still be able to hear some road noise.
About tyres, I have no suggestions. My car has the standard 205/65r16 bridgestone's and according to some latest test they were the best all arounder (best top score).

[IronSoil]

I am not sure if he did the front footwells. I think he did the rear wheel arches.

The total time he spend on the isolation was almost 9 hours.

I will ask him about the front footwells.

I think the only way to get the tire noise down is to buy more silent tires. I think I need to go down to the size of tires that you Rasmus have...:

[Rasmus]

Well, 50kgs is a hell of a lot of isolation materials, so he must have put them in useless places if there is still a lot of road noise going in your car.
Or maybe you are trying the car on rough tarmac? We have a lot of rough surfaced roads here in Estonia and even the quietest of cars produce hearible noise on these roads.
16" are more comfortable and probably a bit quieter, but changing all the wheels and tyres is quite a price, I suggest you try driving a Civic similar to your own and see if there is a difference in road noise before you start changing tyres.

[IronSoil]

Yes the roads here in Finland has alot of rough tarmac, and the car is more quiet on better tarmac.

I will see if I go and testdrive a Civic at a car dealer to see if there is any difference in road noise.

I just wish I would have the money to buy a Lexus. I test drive a RX300 a few years ago and it was so quiet But then the price difference is another too compared to the Civic

[WavyD]

Originally Posted by IronSoil

Yes the roads here in Finland has alot of rough tarmac, and the car is more quiet on better tarmac.

I will see if I go and testdrive a Civic at a car dealer to see if there is any difference in road noise.

I just wish I would have the money to buy a Lexus. I test drive a RX300 a few years ago and it was so quiet But then the price difference is another too compared to the Civic

When you check that they did the wheel arches, make sure that the suspension mount turret tops have also been done. A lot of sound can be transfered through the top mounts and into the chassis. (Both front and rear need covering. Two layers would be best at these points).

[NorCivic06]

Originally Posted by IronSoil

What brand of tires could be the most silent ones and would still be good tires?

I too have Michelin tyres, and they are very noisy. I've been thinking about changing them. But I think I'll wait until next year. I think I can cope with it.
But these are some tyres that at least are promoted as comfort and quiet tyres: Durun A-one, Durun sport one, Roadstone N 3000 and Roadstone N 7000.
Note I haven't tried any of them. So I cannot tell you if they are any good on our Civics'. They cost €170-€230 per tyre

[NickG]

I noticed that on some cars like the Ford Focus, they have something which looks like nylon carpet in the wheel arches on the OUTSIDE of the car. This seemed to make a big difference and I found the Focus had much less tyre noise than the Civic. For instance the civic is really loud if you drive over gravel, sandy or wet roads as you can hear each tiny stone hitting the wheel arch. The fact that this sound is so clear must mean that a lot of the tyre noise is coming in this way too.

Perhaps someone should try putting some nylon carpet on the wheelarches to see if this helps (I can't really try this on my lease car).

[lobey dosser]

Not too sure I'd go along with NickG's suggestion for two reasons.

1) I thought the Focus had about the same amount of road noise as the Civic. I had a lot of complaints from rear seat passengers that they couldn't hear conversation from the front passengers in my Mk1 Focus. Also, as a rear seat passenger in a Mk2 Focus, I can confirm there's a fair bit of road noise from the rear arches that did make conversation difficult.

2) Before I ever bought the car I wasn't happy with the nylon carpet stuff in the arches. I figured it would hold the damp and, being hard against the inside of the arch,3 would encourage rust.
And so it proved, as mine started to show rust bubbles around the rear wheel arches from about 6 years old.
Not a problem if you change your car before then, though.

[Rasmus]

Supposedly quite a lot of cars use some extra insulation on the wheel side of the wheelarch. I have heard of sound isolation kits for the Accord and Mazda 6, which supposedly do help a lot.
I too think that using some cloth there will probably keep the area damp and therefore prone to rusting - this problem is obviously more serious with Fords and their poor paint quality (last Mondeo's and Focuses had some rust issues).
However, there are some special materials that can be used instead of nylon - such as spray bitumen mixtures or brush-on bitumen.
To do this, you would have to remove the plastic liner inside the wheelarches and thoroughly clean the surface and then just apply a few layers on the metal area. This should have a great effect on road noise but it will also be protective against rust and stones chipping and denting the wheelarches. The original liner should go back afterwards, obviously.
I will probably do this all sometime later, at the moment I am looking forward to installing a sub and better rear speakers.
But for now, I am off to WRC Rally Deutschland and Prague in my car.
Got a cruise control installed for 500 euros and am really looking forward to meeting the autobahns

[FWH]

Originally Posted by Rasmus

I have heard of sound isolation kits for the Accord and Mazda 6, which supposedly do help a lot.

I drove a Mazda 6 on a road trip through Estonia, Latvia and Lithuania and I thought it was pretty quiet.
Could have done with sat-nav got very lost in Riga!

[NickG]

Originally Posted by lobey dosser

2) Before I ever bought the car I wasn't happy with the nylon carpet stuff in the arches. I figured it would hold the damp and, being hard against the inside of the arch,3 would encourage rust.

On the Ford Focus, the wheel arches are plastic - just like they are on the Civic! Plastic can't rust so I really don't know what you're talking about. Obviously nobody would put carpet on steel wheel arches as it would rust within months as you say. LOTS of cars are starting to have this Nylon carpet so the manufactures obviously don't think it will cause any problems or they wouldn't do it. They are the ones that have to pay out for the 5 year bodywork corrosion guarantee that most cars have now.

Originally Posted by Rasmus

I too think that using some cloth there will probably keep the area damp and therefore prone to rusting

What exactly will rust? I'm talking here about the inside of the wheel arch - the bit that faces the tyre. It's made of plastic and will not rust in a thousand years! Plastic can not rust - I promise you!

My Civic definitely has more road noise than my Focus did - and by quite some way. Perhaps this is due to the 17" alloys rather than the 15" alloys I had on my Focus. Or possibly the noise of the 2 litre engine in my focus just drowned out the road noise at motorway speeds so I didn't notice it The Focus had more wind noise because of it's tallness and not particularly aerodynamic shape - but this noise clearly came from the door pillar area rather than the road/tyres.

[lobey dosser]

Originally Posted by NickG

On the Ford Focus, the wheel arches are plastic - just like they are on the Civic! Plastic can't rust so I really don't know what you're talking about............. They are the ones that have to pay out for the 5 year bodywork corrosion guarantee that most cars have now.

I'm talking about the vertical (outside) face of the wheel arch which in the Civic is plastic and in the Focus (mk1) is painted steel.
i.e. if you are looking at the car from the side it's the part that some civic owners are having painted to match the car.

On the Ford, the steel side panel of the car body turns under to form the the first half-inch of the wheel arch that faces the tyre. This forms a "shelf" that the nylon matting sits on. The outer edge of the matting therefore rests against the inner face of the steel side skin of the car and, in my opinion, holds the dampness against the metal.
Mine had very visible rust bubbles around both rear wheel arches when viewed from the side. There was no rust around the front arches which do not have the matting.
QED IHMO

Also read my post properly -
I indicated that the rust wasn't visible until the car was about 6 years old. Therefore your point about the 5-year corrosion guarantee is about as useful as the guarantee itself.

[FWH]

I think you will find that the anti-corrosion warranty only applies to rust HOLES caused by rust coming from the inside of the car. Not surface rust on an inner sufracce due to chips.

[Rasmus]

Back from my trip to Germany and the Czech Republic. Over 2 weeks I managed to cover 5900km's - quite a trip.
I must say that adding the sound isolation and cruise control have paid off - covering long distances isn't too uncomfortable or noisy (just as long as I don't keep the rev counter at 4000rpm's).
Maximum speed of my 1,8 - 212km/h on the speedo and 206 according to the gps (Garmin Nüvi).
The funniest thing is that all this time I wasn't allowed to drive - Estonian police had prohibited me from driving and if any cops would have bothered to stop me and check in the database then I would have been buried in troubles. But the driving ban is over now and so are my dark days of having to constantly look out for cops.

Anyhow, last week I decided that I really need some bass in my car so I bought all the necessary things - new speakers for rear doors (Autostudio), speaker rings, 5m of speaker wire, some more vibroplast and GAS active woofer tube.
I took great care in adding vibroplast to all the areas around the speaker (on the sides of the rings as well), fed the wires through doors and hid them away under the carpets and fitted some clip-on plugs for the wires so I could remove the sub easily.
I took signal from both of the rear speakers as I had to change both of the rear speakers and I took both the power and remote from the rear accessory plug (the woofer is 80w rms and has a 10A fuse, so it shouldn't need more).
The woofer works fine - although it isn't the most powerful one I've come across. The main objective - nicer acoustics throughout the range has been achieved and if I do want a heftier sub in the future all I have to do is add a proper power cable and a fuse.
I will try to add some pictures soon, have been too busy to take any.

[terrypcl]

HI Rasmus,

I found one more material called dynamat. They are making big claims.
Can you advice me on that.