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Discussion starter · #361 ·
GTMat Onyx

Actual Measurements

Total Thickness - 80mil

Constraining Layer Thickness - 4mil

0.57 lbs per square foot

Notes - Very very gummy butyl. Almost like the real sticky chewing gum. Odd choice of backing paper, but it works. This one is tricky. On first look at the frequency response graph, it doesn't look much better that GTMat Ultra (80mil). However, comparing the two waterfall plots, the vibration decays much better than GTMat Ultra.

Bare Metal Frequency Response


Damped Metal Frequency Response


Overlay of Undamped Metal vs Damped Metal Frequency Response


Bare Metal Waterfall


Damped Metal Waterfall
 
Discussion starter · #362 ·
So, there's a couple of things about the last tests that I wanted to expand on, one thing that I have learned, and one thing that I want everyone to take away from this.

The first thing, something that I have learned, is you can't tell how something is going to perform by their published specs. A thick constraining layer is great, decent butyl thickness is nice, and all butyl is a good thing. But, even with all those things, the differences in the butyl formula can make or break a product.

Looking at the tests from last night, STP Gold, and GTMat Onyx, are close enough in published specs that they should have performed similar. But, in the situation that I am testing under, Gold tested significantly better in every respect. There was a hint that this might happen before actually testing when I was measuring each one, as Gold was 48% heavier than Onyx, even though Gold was only 6% thicker, and had the same thickness of aluminum. But, that's not conclusive either, as Dynamat, the lightest butyl product so far, performed better than Stinger Roadkill Expert, which is both heavier and thicker, and has a thicker aluminum layer.

So, what have we learned so far? There is no way to tell from constraining layer thickness or butyl thickness, or weight, how well a product performs compared to another. Meaning testing is needed, and this makes me more determined in the future to test again, with a better set up.
 
Discussion starter · #363 ·
So the second thing that everyone needs to take away, is that the waterfall plots are far more important than the frequency response. Last nights tests are a perfect example as well, if we compare GTMat Onyx to GTMat Ultra (80mil).

Looking at the frequency response graph, we see that Onyx lowered amplitude by 2.89db at the resonant frequency. It also lowered the resonant frequency by 12.5hz. Ultra (80mil) lowered amplitude at the resonant frequency by 3.29db, and lowered the resonant frequency by 5.7hz. Seems pretty close right?

Lets look at the amplitude over time. From the initial impulse to the 100ms mark, Onyx lowers the amplitude at the resonant frequency by 11.1db, while Ultra (80mil) only lowers it by 8.1db. Going further out in time, they separate themselves even further. From impulse to 200ms, Onyx lowers amplitude at the resonant frequency by 30.3db, which Ultra (80mil) only lowers it by 22db. Going to 300ms would separate the two even further.

While the initial impulse changes between the two aren't significant, the changes in amplitude over time, are. The difference is audible. Ultra (80mil) still rings, while Onyx decays much faster.
 
Me like what I'm seeing.

Keep this up
 
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Discussion starter · #366 ·
Damp Pro should be tested tomorrow, along with Raamat, STP Silver, and Memphis Mojo Mat.

That said, keep in mind, I still have heat testing to do, and that will play heavily on how I rank these products in the end. The best damper is no good in my eyes if it can't stay attached to the roof when its 110 out, or on the firewall.
 
You are simply an awesome person for doing this testing any making your findings public. Thank you! I look forward to reading the results!

The worst Instagram you've ever seen.... @ dawiz711
 
Discussion starter · #369 ·
Absolutely, there will be a results thread, where everything is put together. I've been working on it as I go, it should be in PDF format. Right now, were looking at close to 75 pages for the full in depth results of all products, that said there will be a simple speadsheet at the beginning with a simplified version.
 
Great! I had to read a few pages back to catch up with some of the brands tested.

Sorry but Im not so great at reading the graphs and figuring out the fast decay I just need to get used to it and now I just look at the specs read the conclusion since most grraphs are similar. Will it be possible maybe in the final summary also nominate the better performer not just on the numbers and sonic difference but maybe on better Performance based on lighter weight assuming any of them is worth mentioning or a case applies.
thanks.
 
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Discussion starter · #371 ·
This weekend I worked through the data to come up with a way to rank the products based on vibration damping performance. Lots and lots and lots of zooming in, zooming back out, windowing things differently, etc. I'll work on getting those online by mid week. Also tested Damp Pro, Memphis Mojo Mat, and STP Silver. Some surprising results, I'll get them up after work.
 
Discussion starter · #373 ·
Second Skin Damplifier Pro

ACTUAL MEASUREMENTS

Total Thickness - 75mil

Constraining Layer Thickness - 6.25mil

0.55 lbs per square foot

Notes - Seems a little under on total thickness. 75mil is the thickest measurement I made, some measurements were around 70mil. I'm going to cut more pieces from around the sheet and measure them as well. Constraining layer was just barely under. Weight was under as well.

Bare Metal Frequency Response


Damped Metal Frequency Response


Bare Metal vs Damped Metal Frequency Response


Bare Metal Waterfall


Damped Metal Waterfall
 
Discussion starter · #374 ·
Memphis Audio Mojo Mat

ACTUAL MEASUREMENTS

Total Thickness - 80mil

Constraining Layer Thickness - 4mil

0.67 lbs per square foot

Notes - Stick butyl, not as gummy as Onyx or Stinger. Feels relatively stiff.

Bare Metal Frequency Response


Damped Metal Frequency Response


Bare Metal vs Damped Metal Frequency Response


Bare Metal Waterfall


Damped Metal Waterfall
 
Discussion starter · #375 ·
STP-Atlantic Silver

ACTUAL MEASUREMENTS

Total Thickness - 80mil

Constraining Layer Thickness - 3mil

0.74 lbs per square foot

Notes - Again, all STP has the cleanest removing butyl. Thin aluminum layer.

Bare Metal Frequency Response


Damped Metal Frequency Response


Bare Metal vs Damped Metal Frequency Response


Bare Metal Waterfall


Damped Metal Waterfall
 
Wow. The results for Damplifier Pro are surprising. I expected more out of it. I have a large order of audio technix coming at the end of the week, hope I made a good choice.
 
Discussion starter · #380 ·
There's a few things going on here. If you just look at the the frequency response graphs, it doesn't appear that Damp Pro is a very good damper, but that would be misleading, as the difference between frequency response graphs is not what tells how good a damper a product is. The Damped Waterfall plot is what shows that. I know its hard to read them, but those are what needs to be looked at first.

The frequency response plot shows something else. For instance, one product puts up a good number when you compare frequency response plots, but performs poorly when looking at the waterfall plot. This means that over time, the product does a poor job at damping vibration. The big number between frequency response plots represents the instant amplitude reduction between undamped metal and damped metal. This can be caused by a product acting more as bracing, increasing rigidity, while not damping vibration as well as other products that don't increase the rigidity as much.


Give me a few minutes and I'll expand, I'm putting the numbers together now.
 
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