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Really? I emailed him two weeks ago on Wednesday, received a reply back from him Thursday morning, paid that afternoon, and order was shipped out that evening. Was very quick response and shipping.
 

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I haven't been able to get a hold of Don for a while so I went with STP.
Ya, it took him a bit to get back to me. I emailed him on a Thursday, hadn't heard back by Monday, re-emailed him and he got back to me the same day. He said he is super busy.

All things considered it took about a week and a half between my initial email and him sending me my order. I did place a large order and had a ton of questions though.
 

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Discussion Starter #27
I can't believe NO ONE picked up on this...
I lol'd, just didn't post it lol.

GLN305, I got the Roadkill in today, looks good, thanks for helping out.



So far, I have a sheet each of Alphadamp, SDS, Lightning Audio, and two 6x6" sheets of Roadkill Pro. I'll go by the local audio shop that swears by dynamat tomorrow, and see if they can hook me up, if not i'll just pick up the smallest amount they'll sell me. Need to get some peel n seal too.

With my motocross bike going up for sell today, I'm going to try to pick up an omnimic setup before I start testing, so I can make sure that each test is even more consistent.
 

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Glad it got there, I'll see what else I can come up with.

I lol'd, just didn't post it lol.

GLN305, I got the Roadkill in today, looks good, thanks for helping out.



So far, I have a sheet each of Alphadamp, SDS, Lightning Audio, and two 6x6" sheets of Roadkill Pro. I'll go by the local audio shop that swears by dynamat tomorrow, and see if they can hook me up, if not i'll just pick up the smallest amount they'll sell me. Need to get some peel n seal too.

With my motocross bike going up for sell today, I'm going to try to pick up an omnimic setup before I start testing, so I can make sure that each test is even more consistent.
 

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This is an interesting experiment and I put some effort into one very similar, though smaller scale. I've always wanted to do something more inclusive and a little more serious though. I would really enjoy collaborating on this experiment.

This report from E-A-R Specialty Composites is one of the most accessible resources I found on the subject. It is written in very simple terms and is easy to read, but has some great details about how CLD works and what is important when considering them.

This report from Roush Industries is more technical but illustrates a simple method for determining the damping factor of a system graphically without using expensive software or hardware (you already have an accelerometer, just plug it into a spectrum analyzer like TrueRTA or REW).

You mention using a 'scope for measurements, but I believe the best method is a spectrum analyzer and calculating the damping factor as discussed in the article above. I have cleaned it up a bit and summarized the method in my experiment and it can be found here in the beginning of my build thread.

You mention using 22ga sheet metal. I'm not sure it would be the best test substrate. Most sheet metal in a car is much thicker, no? I realize that thicker material is substantially more expensive, but it is a very important factor. The effectiveness of a CLD is significantly related to the thickness of the substrate vs the thickness of the stiff backing (aluminum in most cases).

-J
 

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You mention using 22ga sheet metal. I'm not sure it would be the best test substrate. Most sheet metal in a car is much thicker, no? I realize that thicker material is substantially more expensive, but it is a very important factor. The effectiveness of a CLD is significantly related to the thickness of the substrate vs the thickness of the stiff backing (aluminum in most cases).

-J
Most floors and rockers average between 16ga and 18ga but I think 20ga - 22ga is about average for door thickness. I know 22ga is what most body shops use for welding panel repairs on the newer cars. It will differ from car to car or truck but I would think it should be fine for this test.
 

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Ya, it took him a bit to get back to me. I emailed him on a Thursday, hadn't heard back by Monday, re-emailed him and he got back to me the same day. He said he is super busy.

All things considered it took about a week and a half between my initial email and him sending me my order. I did place a large order and had a ton of questions though.
It's been a couple of months and multiple emails and nothing. I even tried PMing him here and nada. :confused:
 

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So far, I have a sheet each of Alphadamp, SDS, Lightning Audio, and two 6x6" sheets of Roadkill Pro. I'll go by the local audio shop that swears by dynamat tomorrow, and see if they can hook me up, if not i'll just pick up the smallest amount they'll sell me. Need to get some peel n seal too.
I can send you a 12x12 tile of Dynamat Xtreme with the GT stuff if that helps?
 

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Discussion Starter #35
This is an interesting experiment and I put some effort into one very similar, though smaller scale. I've always wanted to do something more inclusive and a little more serious though. I would really enjoy collaborating on this experiment.

This report from E-A-R Specialty Composites is one of the most accessible resources I found on the subject. It is written in very simple terms and is easy to read, but has some great details about how CLD works and what is important when considering them.

This report from Roush Industries is more technical but illustrates a simple method for determining the damping factor of a system graphically without using expensive software or hardware (you already have an accelerometer, just plug it into a spectrum analyzer like TrueRTA or REW).

You mention using a 'scope for measurements, but I believe the best method is a spectrum analyzer and calculating the damping factor as discussed in the article above. I have cleaned it up a bit and summarized the method in my experiment and it can be found here in the beginning of my build thread.

You mention using 22ga sheet metal. I'm not sure it would be the best test substrate. Most sheet metal in a car is much thicker, no? I realize that thicker material is substantially more expensive, but it is a very important factor. The effectiveness of a CLD is significantly related to the thickness of the substrate vs the thickness of the stiff backing (aluminum in most cases).

-J
Jazzi, I'll check those links when I get home from work. I definitely don't plan to use a scope for the actual measurements, just to verify functioning of the accelerometer. For everything else, a spectrum analyzer will be used. This is going to be a huge undertaking, so I'd welcome any help I can get. So far, I think I'll have at least 15 different CLD brands/lines. My main concern is making sure to get test results at 1/48 octave resolution. Reason being, what happens if Brand A, lowers resonance from 50hz to 40hz, and reduces amplitude by 6db. Then Brand B, lowers resonance from 50hz to 45hz, and reduces amplitude by 3db. Brand B could show up as better than Brand A if your only getting info for every third of an octave.


I chose 22 gauge mostly due to cost, and relative thickness to car doors, as that's usually the first spot treated, and in many cases the only spot. But also, since my goal was more to see which deadener works the best, I would think that the deadener that works the best on 22 gauge would still work the best on 16 gauge as well when simply talking about effectiveness relative to the other brands (even though the absolute numbers would be different). I do have a couple of CLD constraining layer tests I'd like to run as well, which I'll expand on once I figure out the best way to test them.



Tracie, that would be great if you have some you don't need. I'll email you today when I'm home from work, around 1pst.


Thanks South East Customz, I'll let you know when it gets here.
 

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Chris,

Good to see you taking on this potentially monumental task. You know I am local, so if you ever need a "lab assistant" just give me a call. I'd be happy to come help you out with any of the fabrication or testing. I can bring along what photo equipment I have to try and help document, if need be. Which shop locally were you going to attempt to score some deadener from (you can just name a street/area if you don't want to name names)?

On a personal note, I would love to see the Knu Konceptz Kno Knoise and/or Kno Knoise Kolossus tested. I have tried a couple of times to get a hold of Don at SDS and never gotten a response. I plan to purchase from Knu myself, but haven't placed the order yet. If I can order soon, I'll see what I can do about slipping in an extra sheet to the order to pass along.
 

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Discussion Starter #39
Thanks Dustin. I haven't stopped by any shops yet, but I figured I would see what Zam's was using. I was going to try to get some dynamat from California Car Stereo, but Tracie from GTMat sent me a square, although I'd really love to find some Dynaplate. I'm not spending $175 on it though, and that seems to be the cheapest it goes for, since they only sell larger quantities. If you have any extra Knu stuff, that would be great. If not, we'll see where the budget falls.

Photo help would be great, my camera works, but its still a point n shoot, although it takes 1080 video. I think it does video better than pics.

Tracie, I got your package today, thanks again for helping out.

So, what I have so far is,

2 - Stinger Roadkill Expert Tiles
1 - SDS CLD Tile
1 - Alpha Damp Tile
1 - Lightning Audio Dead Skin Tile
1 - Dynamat Xtreme Tile
1 - GTMat Onyx
1 - GTMat Pro 50 Mil
1 - GTMat Ultimate 80 Mil
1 - GTMat Pro 110 Mil



Jazzi, when I get some more time, I'm going to PM you. I was hoping to meet up at Bings grand opening, but just saw you wont be able to make it.
 
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