* Ask Don of SDS *

[Aaron Clinton 2,372]

I spoke with Don of SDS and we thought this would be a nice addition. As we have a dedicated Sound Deadening section here, this topic is meant for technical questions you want to ask Don directly to help add to the resource of this section. No, this is not a topic about SDS product pricing and such, that is what Don's email is for. Hopefully this will be a nice focused discussion to help people understand the concepts and purpose behind different materials and products available.

[Shogen 325]

I know it's been asked bfore but to start off the thread..

Don,

What is the best way to keep outside noise from entering the cabin? Which should come first, doors, roof, floors, wheel wells from outside? Is this all vehicle dependent? Thanks

-Danny

[Sencheezy 689]

Don,

What is the difference between your product and the many others out there? I am fully aware of your excellent customer service. But talking strickly product here, what can someone benefit from your product vs any others out there on the market? What is inside your materials that make it a better choice? What testing on these products can ensure us the consumers, that we are making the best decision when choosing your products vs anybody else?

Edited January 26, 2011 by Sencheezy

[Rudeboy 152]

I know it's been asked bfore but to start off the thread..

Don,

What is the best way to keep outside noise from entering the cabin? Which should come first, doors, roof, floors, wheel wells from outside? Is this all vehicle dependent? Thanks

-Danny

Danny,

Some of that depends on how you define "outside noise". If you mean noise that doesn't come directly from your vehicle or its interaction with the environment, doors would be first since they let in most traffic noise.

Doors make a good first project. They can be done without disturbing the rest of the vehicle. I know from personal experience that you can drive a car for days without trim panels. On warm days you can drive without glass Noise rejection treatments involve installing a barrier. If you hang this layer from the inner skin and have door mounted speakers, you'll also be isolating the front and rear wave coming from the cone, improving speaker performance.

An interesting thing happens when you start by treating one area. In a noisy car, you are sitting in a swirl of sound coming from every direction. This makes it difficult to localize the sources. Treat just the doors and you are likely to be able hear engine, exhaust and tire/wheel noise better than you could before. It's not louder, just easier to localize and identify.

That leaves noises generated by the vehicle - engine, exhaust and its interaction with the environment - tire/wheel and wind, maybe rain too.

Engine, exhaust and tire/wheel noise are complicated. The firewall and floor are where they penetrate, but not exactly as we tend to think. Engine and exhaust noise do hit the passenger compartment in a direct line, but they also reflect off the pavement, meaning they even enter through areas from which you can't draw a straight line back to the source.

Tire noise is especially interesting. Most of us think that most of it comes in through the wheel wells. That's led to all sorts of exterior treatments that are supposed to avoid the complication of getting to the interior surface of the floor. It seldom makes an audible difference. The important point is that tire noise starts at the contact patch with the pavement and radiates up in every direction from there. A lot of the sound that would otherwise pass through the wheel well is blocked by the tire and wheel. The reality is that tire noise enters through most of the floor.

Interestingly and despite years of tradition pointing in exactly the opposite direction, you generally don't need much supplemental vibration damper on the floor of a vehicle, especially if you don't plan to remove and replace the factory application. The floor is almost always braced and reinforced in a variety of ways that make it much less susceptible to resonance than other areas like the doors, roof and quarter panels. Add the bolted down seats and the weight of a human being or more and you are most of the way there. A barrier layer is always going to yield the biggest improvement.

Spare tire wells are another area that have been traditionally over treated to the extreme. The usual approach is to remove the spare, tap the sheet metal and marvel at the flimsy construction and extreme resonance. Many wheel wells WILL benefit from some supplemental treatment. The confusion results from the fact that the spare itself is part of the manufacturer's NVH treatment. With the spare in place, the well has completely different characteristics.

The roof is interesting. Glass will always be the weak link in any noise attenuation program. This isn't as big a problem as we might fear because most of the noise we are concerned about strikes the vehicle below the glass line. What this means in terms of treatments is that a barrier isn't going to help much unless you are frequently exposed to noise sources directly overhead. I had one customer who spent a lot of his day driving around an airfield. For most of us it isn't a problem.

Resonance can be a major problem for the roof, especially since it is such a large panel, right above your head. This resonance can be excited by a wide variety of sources. My rule is to tap on the roof from outside the vehicle. If it rings, treat it. If not, it's probably not worth the effort.

[Rudeboy 152]

Don,

What is the difference between your product and the many others out there? I am fully aware of your excellent customer service. But talking strickly product here, what can someone benefit from your product vs any others out there on the market? What is inside your materials that make it a better choice? What testing on these products can ensure us the consumers, that we are making the best decision when choosing your products vs anybody else?

This shouldn't be an SDS product specific thread. I'll be posting some test results for CLD Tiles on the SDS site in the next few weeks that should show that the adhesive used has been tested more thoroughly than any other product on the market. Going through the catalog, product by product, would be beyond the intended scope of this thread but I will try to get more data on the SDS site. I'm confident enough that every product I sell belongs in the top tier of this category that I happily send free sample kits to anyone who requests them (in the US). Nothing like hands on to evaluate quality.

[Kanaworm$ 292]

Great addition!

[sefugi 166]

Great addition!

X2

[Shogen 325]

I know it's been asked bfore but to start off the thread..

Don,

What is the best way to keep outside noise from entering the cabin? Which should come first, doors, roof, floors, wheel wells from outside? Is this all vehicle dependent? Thanks

-Danny

Danny,

Some of that depends on how you define "outside noise". If you mean noise that doesn't come directly from your vehicle or its interaction with the environment, doors would be first since they let in most traffic noise.

That leaves noises generated by the vehicle - engine, exhaust and its interaction with the environment - tire/wheel and wind, maybe rain too.

Engine, exhaust and tire/wheel noise are complicated. The firewall and floor are where they penetrate, but not exactly as we tend to think. Engine and exhaust noise do hit the passenger compartment in a direct line, but they also reflect off the pavement, meaning they even enter through areas from which you can't draw a straight line back to the source.

Tire noise is especially interesting. Most of us think that most of it comes in through the wheel wells. That's led to all sorts of exterior treatments that are supposed to avoid the complication of getting to the interior surface of the floor. It seldom makes an audible difference. The important point is that tire noise starts at the contact patch with the pavement and radiates up in every direction from there. A lot of the sound that would otherwise pass through the wheel well is blocked by the tire and wheel. The reality is that tire noise enters through most of the floor.

Specifically on the "noise reflection from pavement".. I was tempted to look more into adding Cascade to the outside of my vehicle, under carriage areas that were as flat and had seams joining them together... Basically it is like Second Skin's sludge but a little thinner which could be applied by aerosol and was able to withstand the elements of outside qualities... This was the idea that adding mass to the outside panels would seemingly "deflect" alot of the road noises and sounds similar coming from random directions which could not be measured or tested specifically... Some reported improvements which provided no audible increase in audio equipment but neutralized the added environment noise more than just adding MLV to the floor panels... True or not I cannot confirm, but it could be possible... Anything truth to it? Would it be a waste of labor and money to try this theory out?

[smashedz28 110]

this will be great, such a knowledgeable guy here. were very lucky.

[Rudeboy 152]

Specifically on the "noise reflection from pavement".. I was tempted to look more into adding Cascade to the outside of my vehicle, under carriage areas that were as flat and had seams joining them together... Basically it is like Second Skin's sludge but a little thinner which could be applied by aerosol and was able to withstand the elements of outside qualities... This was the idea that adding mass to the outside panels would seemingly "deflect" alot of the road noises and sounds similar coming from random directions which could not be measured or tested specifically... Some reported improvements which provided no audible increase in audio equipment but neutralized the added environment noise more than just adding MLV to the floor panels... True or not I cannot confirm, but it could be possible... Anything truth to it? Would it be a waste of labor and money to try this theory out?

Premature post. Cascade and Second Skin sell very good products. All of the liquids and pastes are vibration dampers. As I mentioned, you don't need a lot of supplemental vibration damper on the floor. That means you'd need to use these products as barriers. They will be less effective in this application since they are tightly bonded to the sheet metal.

More importantly, a barrier's performance depends on how much it increases the mass of what is already there - you need to double mass to gain an audible improvement. Adding 1 lb/ft² to sheet metal that starts around 1/2 lb/ft² does that. Any idea how thick the application of a liquid product would have to be to get to 1 lb/ft²? I don't remember, but it think it is 6mm or so, roughly 1/4" inch. I can't even guess how many cans of an aerosol it would take to coat the entire underside of even a small car to that thickness. You would need to cover the entire underside since sound will bend around a more difficult barrier to follow an easier path.

Here's something else to consider when you contemplate a treatment that needs to be permanently bonded to a vehicle's sheet metal. What happens if you need body work? I've been wondering about this for some time and is why I encourage anyone who isn't building a one purpose or disposable vehicle to make as few permanent changes as they can to get the results you want. I've been sharing a building with a body shop and now have an informed answer - it can make a minor repair a major repair that insurance won't cover. PDR won't work and panels that could be repaired will have to replaced because of the time required to remove layers of vibration damper. Since there's no performance advantage, why do it?

[NDMstang65 403]

Don,

I'm going to need some product here shortly, what is the best way to contact you? (Can't get the website to load)

Thanks!

Nick

[Julian 641]

Don,

I'm going to need some product here shortly, what is the best way to contact you? (Can't get the website to load)

Thanks!

Nick

[email protected]

[tommyjiggallow 0]

Don,

What is the difference between your product and the many others out there? I am fully aware of your excellent customer service. But talking strickly product here, what can someone benefit from your product vs any others out there on the market? What is inside your materials that make it a better choice? What testing on these products can ensure us the consumers, that we are making the best decision when choosing your products vs anybody else?

This shouldn't be an SDS product specific thread. I'll be posting some test results for CLD Tiles on the SDS site in the next few weeks that should show that the adhesive used has been tested more thoroughly than any other product on the market. Going through the catalog, product by product, would be beyond the intended scope of this thread but I will try to get more data on the SDS site. I'm confident enough that every product I sell belongs in the top tier of this category that I happily send free sample kits to anyone who requests them (in the US). Nothing like hands on to evaluate quality.

Free samples! Now thats what I'm talking about.

[Deto1992 5]

Since installing my new components, I have been hearing fairly prominent rattling coming from my doors. I was just wondering if this rattling has to do with my panels resonating or could it just be the plastic snap on peices that come standard in most vehicles (window controls and surrounding plastic pieces)? If it turns out to be my panels, would the CLD tiles be enough to significantly reduce the resonating?

[ssh 924]

Since installing my new components, I have been hearing fairly prominent rattling coming from my doors. I was just wondering if this rattling has to do with my panels resonating or could it just be the plastic snap on peices that come standard in most vehicles (window controls and surrounding plastic pieces)? If it turns out to be my panels, would the CLD tiles be enough to significantly reduce the resonating?

It doesn't take a Rocket scientist, or Don in this case to tell you it could be both your door panels and plastic snaps or either. No way for someone across the country to be able to pinpoint your exact source of rattling.

Get a few clds to control panel flex, a layer of mlv (if you want to deaden it, door panels already off mine as well do it.), and ccf to decouple the plastic panel from sheet metal.

You could even get some of the butyl to put on your plastic snaps so there not shaking about.

At least that's what I would do

[Rudeboy 152]

Since installing my new components, I have been hearing fairly prominent rattling coming from my doors. I was just wondering if this rattling has to do with my panels resonating or could it just be the plastic snap on peices that come standard in most vehicles (window controls and surrounding plastic pieces)? If it turns out to be my panels, would the CLD tiles be enough to significantly reduce the resonating?

Sorry I missed this. The really important concept to grasp about any rattle is that it is always two or more hard objects moving and making intermittent contact. Seems obvious but keeping that in mind helps when trying to track them and that's really what you need to do to kill them.

Vibration dampers, like CLD Tiles have been promoted as a cure for rattles. This approach may or may not work. It's always the indirect way to solve the problem. If it works, it works because you have successfully reduced the energy available to move the objects that are making contact. A more surefire solution is to identify the objects and either stop them from moving or put something soft between them to prevent contact. This can be a simple as tightening a bolt or screw, adding a blob of RTV silicone or lining one of the surfaces with foam.

This all boils down to detective work. What is rattling? The best way to find out is to play music or test tones that cause it and then start feeling around with your hands. Does pressing on the trim panel stop it? Probably the trim panel rattling against the inner skin. A layer of CCF between the two will solve the problem. Can you narrow it down to two pieces of the trim panel? Maybe lock them down with some silicone. No luck? Try the latch handle and lock nob - could be a cable or actuator rod.

[Deto1992 5]

Since installing my new components, I have been hearing fairly prominent rattling coming from my doors. I was just wondering if this rattling has to do with my panels resonating or could it just be the plastic snap on peices that come standard in most vehicles (window controls and surrounding plastic pieces)? If it turns out to be my panels, would the CLD tiles be enough to significantly reduce the resonating?

Sorry I missed this. The really important concept to grasp about any rattle is that it is always two or more hard objects moving and making intermittent contact. Seems obvious but keeping that in mind helps when trying to track them and that's really what you need to do to kill them.

Vibration dampers, like CLD Tiles have been promoted as a cure for rattles. This approach may or may not work. It's always the indirect way to solve the problem. If it works, it works because you have successfully reduced the energy available to move the objects that are making contact. A more surefire solution is to identify the objects and either stop them from moving or put something soft between them to prevent contact. This can be a simple as tightening a bolt or screw, adding a blob of RTV silicone or lining one of the surfaces with foam.

This all boils down to detective work. What is rattling? The best way to find out is to play music or test tones that cause it and then start feeling around with your hands. Does pressing on the trim panel stop it? Probably the trim panel rattling against the inner skin. A layer of CCF between the two will solve the problem. Can you narrow it down to two pieces of the trim panel? Maybe lock them down with some silicone. No luck? Try the latch handle and lock nob - could be a cable or actuator rod.

I have yet to do any serious investigation but the rattling ceases when I apply pressure to door panels. I will see if I can find the true source and get back to you when I do. Thanks for the help!

[Infinite913 381]

Don, I am adding another 18 to my truck and I was wondering on a few things! I have my whole car layered with SPECTRUM sludge and I am going with the port up subs up. I will be rocking 2 18" zcons with an 18 cube box tuned to 34hz with 220sq of port area. So my question after giving a little Idea is would it be advisable to add some more deadener to the roof? and if so can you email me a price [email protected] thnx man! If you need anymore Info just PM me!

[1sicls1 0]

Due to forum rules I'm going to keep this to specific questions, however I am interested in pricing and other knowledge so I will email you that request Ok, first off I'll admit new to deadening and I have noticed on alot of forums and also certain company's go by the rule that more is better. I can't tell you the numerous pictures I have seen that the WHOLE interior is covered in dynamat logos or the off brand foil type deadener. Then I go to your site and did the "long story" reading and found out that this is wrong That being said, I would love to see pics that you have (or other forum members) that show this 25% coverage for flat panels. I guess its hard for me to picture this since I have been poisoned by the complete coverage theory. I would love to do just 25% coverage and save a #$%# ton of money. So your saying that if I go this route that it will outperform me doing the entire car? Before I went to your site I came to the conclusion it would take some were between 100-120 sq. ft. to completely cover my car (1999 Camaro Z28) in deadener and around $300-500 then I need a barrier on top of that for another few hundred.... Ummm....no thank you, I have better things to spend my hard earned money on, and then if I did that and I heard "road noises" I would be irate. So I guess I just want to be sure that I'm going the right route here and want to see some examples of this type of coverage. Thank you

[Rudeboy 152]

Don, I am adding another 18 to my truck and I was wondering on a few things! I have my whole car layered with SPECTRUM sludge and I am going with the port up subs up. I will be rocking 2 18" zcons with an 18 cube box tuned to 34hz with 220sq of port area. So my question after giving a little Idea is would it be advisable to add some more deadener to the roof? and if so can you email me a price [email protected] thnx man! If you need anymore Info just PM me!

This brings up topics I'd hope we'd get into in this thread: sound deadening materials in an SPL setup and matching the treatment to the goals. Let's start with extreme SPL.

Introducing high pressures into a vehicle exceeds the manufacturer's design. Something has to give to relieve the pressure. The exact path will be the one with the least resistance. Could be an air leak, could be sheet metal displacement or deformation or most impressively to some, the glass may break.

Because of rules and habit, the traditional reaction has been to start layering on vibration damper. This might help or it might hurt - we've all seen posts describing small gains or small losses. There's no predictable outcome. How can this be?

I can think of two possible mechanisms that could increase SPL: the vibration damper seals air leaks or it adds a small amount of reinforcement to the sheet metal. It's pretty easy to see that both outcomes are inappropriate applications for vibration damper.

It's easier to see how vibration damper can lower scores since that's basically what it is designed to do. Vibration dampers work by converting vibration - which can become measurable sound, into heat - which can't. Even if a vibration damper application increases overall pressures, it does so in spite of converting at least some of the available energy into an unusable form. To predictably improve a vehicle's capacity to hold pressure, seal leaks and brace panels in a way that doesn't bring an offsetting conversion of energy to the party.

Now let's suppose you don't care about numbers on a meter, you like your music loud and you just want to stop your roof from flapping around. The basic solution is still the same: mechanically reinforce it. Vibration damper is an inefficient solution to gross movement. If you use a bracing method that subdivides the roof - metal or wooden "beams" for example, you'll gain something else in the process, you will have divided the roof into smaller panels. Each smaller panel will have a higher resonant frequency that the entire roof did. Vibration dampers are more effective in this range. You'll be able to use less if you are trying to quiet things down and if it's a combination SPL competition vehicle and daily driver, you'll lose less energy to heat.

[Rudeboy 152]

That being said, I would love to see pics that you have (or other forum members) that show this 25% coverage for flat panels. I guess its hard for me to picture this since I have been poisoned by the complete coverage theory.

Aaron's Mazda.

[Godsmack 361]

Don,

I just wanted to say thanks for coming by and answering questions. As I prep to go home and start on a new project, expect many questions from me.

J

[Sencheezy 689]

Don,

I have a question, how do you stop(reduce) the noise coming in the cabin, from the engine? Will this have to involve removing the entire dash, and applying one of your products to the firewall? Or maybe even going overboard, and taken the entire engine out, and applying some kind of product inside the walls of the engine compartment? I have ZERO experience with this, which is my reason for asking for your opinion. What would I have to do to accomplish the best results for a problem like this?

In advance, many thanks!

Edited February 14, 2011 by Sencheezy

[Rudeboy 152]

Don,

I just wanted to say thanks for coming by and answering questions. As I prep to go home and start on a new project, expect many questions from me.

J

Bring 'em on

[Rudeboy 152]

Don,

I have a question, how do you stop(reduce) the noise coming in the cabin, from the engine? Will this have to involve removing the entire dash, and applying one of your products to the firewall? Or maybe even going overboard, and taken the entire engine out, and applying some kind of product inside the walls of the engine compartment? I have ZERO experience with this, which is my reason for asking for your opinion. What would I have to do to accomplish the best results for a problem like this?

In advance, many thanks!

This depends on the vehicle. In most cars and trucks, the only decent noise treatments are behind the dash and on the center tunnel. Very often engine noise comes through the lower firewall and front floor. Remember, it doesn't just travel in a straight line from the engine into the passenger compartment, it reflects off the pavement and comes in through the floor too. It can also reflect off adjacent vehicles and obstacles along the road and come in through the sides of the vehicle.

In any case, treating the floor, from as far up the firewall as you can reach to the front edge of the front seats usually results in a significant reduction. If this isn't enough, it may be worth considering treating the hood. I always encourage people to do the interior treatment first since that will make it easier to localize and identify the remaining problem.