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Old 7th July 2009, 22:54   #601
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I don't get vibrations from the plasic door card as i have mounted directly on the door skin, my target is to minimise sound leakage from the speaker going into the hollow of the door card this is where some frequencies go missing, I can't recall seeing any damping on the door skins of my Safari when i installed my speakers, as far as i remember there was only paint, could be wrong though.
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Old 7th July 2009, 23:18   #602
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Sorry @stefanm, but can't resist asking: did you find the frequencies that went missing in the door?

One cannot fault your logic and actions, boss, but sometimes keeping things very simple gives better results than esoteric measures. Try simplicity, at least you won't lose anything like the frequencies you assumed were lost in the door. One doesn't have to use a cannon to kill a mosquito. One has to assume that the guys who designed the door pad speaker mounting were not ignorant of audio engineering, even if the results are rather common-place for you.
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Old 8th July 2009, 13:14   #603
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Thanks a lot to stefanm & DerAlte. Further questions

Quote:
Originally Posted by DerAlte View Post
The real problem is the wide undamped expanses of the FRP door pad. This could use a decent amount of damping material, or careful FG lining on the inside to stiffen the FRP. This itself would cut down the sympathetic vibrations substantially (feels wierd to feel the sound through the elbow).
What is FG lining and FRP? Sorry dont know these acronyms.

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Originally Posted by DerAlte View Post
Make sure the wires in the door are properly stayed down or glued to the metal with hot-melt. Otherwise, opening the door pad will give you more problems.
Even I have this fear. Is it fairly eady DIY thing to open the plastic door covers or should it be done by a professional? If it is DIY, is there any step by step guide available?

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Originally Posted by stefanm View Post
Now I have a question myself, i am getting my front doors damped on my Safari, probably next week, I am doing both inner and outer skins, I am only doing the fronts for now as they are amped,
stefanm, since you are getting this done yourself, can you take some pictures of the whole process and upload them? It will be really helpful for me and others. Pls do take the pics of your speaker mounts as well.
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Old 8th July 2009, 13:32   #604
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Originally Posted by DerAlte View Post
Sorry @stefanm, but can't resist asking: did you find the frequencies that went missing in the door?

One cannot fault your logic and actions, boss, but sometimes keeping things very simple gives better results than esoteric measures. Try simplicity, at least you won't lose anything like the frequencies you assumed were lost in the door. One doesn't have to use a cannon to kill a mosquito. One has to assume that the guys who designed the door pad speaker mounting were not ignorant of audio engineering, even if the results are rather common-place for you.
The logic is simple the Safari door card has this big void behind the panel, then you also have the void between the door skins, sound waves have many exit points or places for the energy to be absorbed, by mounting on the door skin reduces this issue somewhat, then damping the door skin will reduce this loss even further, next is the issue of the access holes for the winder mechanism, if these are sealed then the cavity behind the door card is no longer an issue, i think this requires some simple fabrication, maybe a piece of mdf screwed and damped, I feel damping the door card will yield minimun results. The Safari has this huge void, which I have never come accross in my 22years of tinkering with car audio, now i'm trying to get the best from my system without throwing money away. In my opinion the Safari has one of the worst stock speaker locations i have come across, this gives quite a tiny sound without some degree of modification, my problem is that once i'm happy with my system, i will always be searching for more, guess thats just my nature

Nitvin have a look in the sound off section, my car is there and there is also another Safari, this has been modded by blueraven i believe.

Regards,

Stefan
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Old 10th July 2009, 00:08   #605
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This being the Sound Deadener and Damping thread I wanted to chime in on my recent experience:

I was in the market for some sufficient damping for my Honda Accord. Now many people say things like the Accord is built pretty solid and doesn't need a lot of damping, but I noticed the difference, and then went crazy!

I found some brands for Rs. 150 - Rs. 325 . (My pockets were nearly empty by the time I budgeted damping!)

So I did a little comparison of my own:

Noise Kill - VFM to the core, excellent for budget applications, easy to apply and an OK effect. Would definitely suggest it for anyone looking for damping as an after thought or someone with a budget system or SPL applications.

Wurth - Decent effect, easy to apply, didn't seem to be much thicker than NK, effect was slightly better, but cost increased dramatically for a whole car. Not too impressed for the cost, the benefit over NK wasn't that great.

The last brand I tested was
Dynamat Extreme - At double the cost of NK and a bit more that Wurth, this seemed to be the looser. HOWEVER boy was I shocked. OK by no means double the thickness of the others, but easy to apply, quite similar to NK in that respect, but what was impressive about DE was it's damping ability. By far the best.

But what about the cost, it doesn't seem VFM at double the price of NK. The interesting thing is that applying double layers of any damping is not so simple, so I decided that one should get the best out of a single layer. Also the adhesive and international acclaim that DE had somewhat lured me in.

Needless to say I finally took the plunge and DEed the entire car. I used 2 bulk packs of DE almost the entire 18 sheets, 12 in the boot alone.

Over 20K damage later, I feel it was all worth it! I just saw the car completely damped and am extremely impressed to say the least.

I definitely recommend Dynamat for the enthusiest who wants the best out of his ICE.
NK is an excellent product if one looks at the cost perspective, but the effect is no where close to DE.

Wurth seemed like a waste of money to me, would suggest NK over it any day.

Cheers

PS: The test performed was pretty pegan, a few large metal pieces were taken the damping material applied to one side, and the another plain metal piece as a control. These were then dropped from an equal height and the sound compared by a panel of 8 people. The results were as follows:

DE was the clear winner with the most muffled clank heard
Wurth was next but far from the effect of DE.
NK was an extremely close 3rd, I personally found NK better than Wurth.

VFM wise NK was voted the winner at half the price of DE, but we did agree that higher end systems would require the added advantages of DE, but that's the realm where budget doesn't matter that much anyway.


PPS: I now want to acquire some accumat from Scosche and any other damping brands which members can suggest to try out this test on them. The material should be easily available in India.


I will try to transfer the pics as soon as possible, but it will take a few days as my lappy seems to have drunk some rain water, need to get that fixed.
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Old 10th July 2009, 09:39   #606
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Quote:
Originally Posted by DocG View Post
DE was the clear winner with the most muffled clank heard
Wurth was next but far from the effect of DE.
NK was an extremely close 3rd, I personally found NK better than Wurth.
Wurth also sells a spray on damping material. 2 cans would cover the front doors well. Another 2 cans will cover the under body of mid sized sedans (City, Accent, etc..). Using a combo of NK (or an equivalent) and this spray on dampig might be an option for those with "champagne tastes and beer budgets". The NK or equivalent goes on first the spray goes on top. For the underbody the spray goes on under the car and the NK goes between the carpet and body.
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Old 10th July 2009, 09:46   #607
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Quote:
Originally Posted by NiTviN View Post
What is FG lining and FRP? Sorry dont know these acronyms.
FG lining is sorta equal to FRP.

FG is bonded with resin otherwise the fibres like loose cotton will fly all over. you get FG in mat and woven form. mat is random FG fibers, woven is like a cloth. Mat offers better strength as the random fibers offers no clear 'line of break'.

FRP is Fibreglass Reinforced Polyester resin. Almost the same as FG with resin depending on the resin used. If the resin used is polyester resin then FG with resin is the same as FRP. Capisce?
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Old 10th July 2009, 12:24   #608
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Quote:
Originally Posted by NiTviN View Post
... What is FG lining and FRP? Sorry dont know these acronyms.
... Is it fairly eady DIY thing to open the plastic door covers or should it be done by a professional? If it is DIY, is there any step by step guide available? ...
I meant laying some fiber glass on the inside of the door pad, which is made of FRP. Navin, the resin in the FRP has platicizers and stabilizers, rendering it flexible to a certain extent even after it is set. The DIY FG resin lacks these, so sets much stiffer.

Opening the door pad is fairly easy. There are about 6 screws around the sides and bottom. After unscewing those, lift the pad slightly so that it pops out of the mechanical catches at the top, Reverse procedure to fit it back.

To lay FG, disconnect the connectors to the switches on the pad, remove the speaker connections and take out the pad. Using spirit or thinner, clean the areas you want to to put FG to remove the moulding lubricant etc. Then lay 2 layers of FG in all the large areas (which bend most when pressed). Add another layer in the largest central area.

There are instructional videos on YouTube on FG application. PM @shreyasma for the address of a shop in VV Puram (near Food Street / Sajjan Rao Circle) who stocks all the necessary stuff.

Quote:
Originally Posted by stefanm View Post
The logic is simple the Safari door card has this big void behind the panel, then ... next is the issue of the access holes for the winder mechanism, if these are sealed then the cavity behind the door card is no longer an issue, i think this requires some simple fabrication, maybe a piece of mdf screwed and damped, ...
Baap re baap! Arrey o Stefan-bhaiyya, please do read up on speaker enclosure creation theory and practice. Hearsay like this results only in moolah going down the drain!!!

The way the Safari (and Indica/Indigo) door speaker mounting is designed, the *whole* cavity - from the door pad to the outer metal skin of the door acts like a slightly-leaky-but-still-sealed enclosure for the mid-bass. (Navin: what is the effect of Vb >> Vas?)

Other cars, like Swift and Palio (I think), mount the speaker on the inner metal skin of the door and, assuming that the mounting ring of the speaker is tightly touching the door pad, the *whole* cavity is the enclosure volume behind the speaker. This is the same arrangement as in Safari.

The MDF ring is used to make up the distance between the inner metal skin and the door pad, and damping it is mere gimmick. Maintaining a seal between the speaker mounting and the doorpad is very important, but since that is rather difficult achieve, an attempt is made to limit the the enclosure to between the inner and outer metal sheets of the door.

IMHO that is a rather costly vain-glorious attempt that doesn't really solve the problem. Sealing the inner skin 'holes' is only a psychological measure - it really does not participate in anything, since any damping material not sticking to anything is an elastic membrane - terribly inefficient as an enclosure wall! Do you realize it will act as a drum skin instead of being a stiff wall? So it is the general "something must be better than nothing" principle which you are paying for.

If you see the original mid-bass mounting in Safari, it is a short angled 150mm tube at the end of which the speaker is mounted. The speaker-mounting flange encounters a right angle bend where it meets the tube, which stiffens it - making an MDF ring redundant.

In your case, the 6.5" RF Punch mid-bass *couldn't* have been mounted in the place meant for 5.25", hence an improvized MDF ring mounting was made by cutting away the original. Quite appropriate, but I like @blueraven's method of mounting it from the front on an MDF plate *without cutting the original mounting* better - at least one can re-mount the original speakers while selling the car. The MDF here is for convenience, not that it makes anything better.

The outer metal skin conducts road noise, and also vibrates in self-resonance mode; put together it is a soft dull hum that takes away the enjoyment of the music by cancelling some of the low-F waves ( no, the frequencies don't get 'lost' anywhere). Damping the outer skin makes sense. Much of the hi-mids and highs come out of the mirror-pod-mounted tweeters; the door cavity is only involved in the mids and lows out of the mid-bass.

Stiffening and damping the door-pad cuts increases the energy efficiency of the speaker system, cutting out stray energy loss from the system.

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... my lappy seems to have drunk some rain water ...
Oh man, how do you guys manage to get into such unhygienic situations!? Doctor Girish, you of all the people should know that to prevent your laptop from getting infections such as Jaundice and Hepatitis, you should make the laptop drink only boiled Aquagard or distilled water. Tut tut, you are not doing your paternal duties well.
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Old 10th July 2009, 17:07   #609
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Hi,

I was looking for damping my Swift. But from reference when checked at Team-BHP recommended shops, none of them were having NoiseKill.

I would appreciate if team members can let me know, where can I buy and install NoiseKill in Bangalore.

regards,
-manju
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Old 10th July 2009, 17:28   #610
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^^ Contact Bass&Trouble.
He will tell you where to look.
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Old 10th July 2009, 18:44   #611
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Thanks I will PM Bass&Trouble.
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Old 11th July 2009, 01:39   #612
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Quote:
Originally Posted by navin View Post
Wurth also sells a spray on damping material. 2 cans would cover the front doors well. Another 2 cans will cover the under body of mid sized sedans (City, Accent, etc..). Using a combo of NK (or an equivalent) and this spray on dampig might be an option for those with "champagne tastes and beer budgets". The NK or equivalent goes on first the spray goes on top. For the underbody the spray goes on under the car and the NK goes between the carpet and body.
Sir the current comparison is only between the damping sheets which I could lay my hands on. The material used was not much, but we used equal amounts of material in each test. The Dynamat was some extra strips lying around the shop. The NK was procured from a customer's car who had some extra lying in the boot. The Wurth was difficult, we had to call in a favor and get a bit off of a friend who happened to source half a sheet of the stuff.

The problem with a spray is that I'd have to buy the whole can, any idea how much a can costs? I have to do the underbody of my Accord.

And besides Navin, if we used NK and then Wurth spray, it would probably be cheaper to use Dynamat in the first place!

Love the fact that you recommend damping, but sir have you experienced Dynamat Extreme?

Quote:
Originally Posted by DerAlte View Post
Oh man, how do you guys manage to get into such unhygienic situations!? Doctor Girish, you of all the people should know that to prevent your laptop from getting infections such as Jaundice and Hepatitis, you should make the laptop drink only boiled Aquagard or distilled water. Tut tut, you are not doing your paternal duties well.
Will try better next time, but torrential rains in Mumbai and requirement of tech at work make it impossible not to lug it around, and I guess she felt thirsty. Sad though since I would never drink rain water, these bad tech children, drinking and eating harmful things at such a young age!

PS: It's actually bad to keep drinking distilled water, boiled is a better option...

Last edited by DocG : 11th July 2009 at 01:52.
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Old 11th July 2009, 11:21   #613
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Quote:
Originally Posted by DerAlte View Post
The DIY FG resin lacks these, so sets much stiffer.

The way the Safari (and Indica/Indigo) door speaker mounting is designed, the *whole* cavity - from the door pad to the outer metal skin of the door acts like a slightly-leaky-but-still-sealed enclosure for the mid-bass. (Navin: what is the effect of Vb >> Vas?)

Maintaining a seal between the speaker mounting and the doorpad is very important, but since that is rather difficult achieve, an attempt is made to limit the the enclosure to between the inner and outer metal sheets of the door.

Stiffening and damping the door-pad cuts increases the energy efficiency of the speaker system, cutting out stray energy loss from the system.
I only use the DIY FG with resin. I find it messier to apply but the seal is often better as one can fold the FG woven sheet into very complex shapes. Then I strenghten any areas I feel need to be strengthend using the FG mat.

Quote:
Originally Posted by DocG View Post
The problem with a spray is that I'd have to buy the whole can, any idea how much a can costs? I have to do the underbody of my Accord.

And besides Navin, if we used NK and then Wurth spray, it would probably be cheaper to use Dynamat in the first place!

Love the fact that you recommend damping, but sir have you experienced Dynamat Extreme?
I have no idea what a can costs.

That is the idea. NK (or any equivalent) + Wurth might offer you the same damping as DE but work out cheaper.

Yes I have used DE more than once. I have aldo used NK and other products.
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Old 11th July 2009, 11:35   #614
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I have a small query! Can the used damping sheet be reapplied, I intend to apply double layer on the inner most layer of the front doors,for that I have to remove the second layer.
Can this be done or new sheet will be required?
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Old 11th July 2009, 13:14   #615
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Quote:
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... I intend to apply double layer ...
1. Why would you want to remove the layer which is already stuck? You could as well lay the 2nd layer on top of the 1st

2. If you really want to remove it without losing the adhesive, you should use a hot air gun (or a good hair dryer) to first heat up an area before lifting it off. Work patiently with a spatula to lift the sheet, otherwise you will land up ripping the sheet. Better to test on a patch before actually doing it
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