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Close to half the vibration damping/noise mitigation threads on other forums are debates about using asphalt based materials as a vibration damper. I’ve spent way too much time during the last 5 years typing and re-typing responses to these questions. Let’s keep it in one place to reduce litter and redundancy. This topic was my introduction to aftermarket “sound deadening”. I had a noisy car, wanted to quiet it down and started to do research. This was 2005. Several respected “authorities” were vocal advocates for asphalt. Part of this came from the belief that products like Dynamat Xtreme were part of a conspiracy to fleece consumers. Part of it was the often repeated “fact” that roofing materials and vibration dampers sold specifically for aftermarket automotive use were exactly the same thing. One cost pennies per ft² and the other dollars so it was worth investigating. Some of you may remember that Sound Deadener Showdown used to be a testing and review site. Since I wasn’t able to find any conclusive answers on the forums, I decided to buy small quantities of every product I could. Two things were immediately apparent: Nobody had ever had their hands on all of these products at the same time or they would have seen the obvious differences. The people claiming that Dynamat Xtreme and roofing materials were exactly the same thing didn’t know what they were talking about. I discovered a few other things very quickly. Many sellers were making outrageous claims. Some were wildly overstating obvious physical characteristics like thickness and mass/area. Others were either claiming outright that their asphalt products were butyl or were using intentionally deceptive descriptions like “rubberized compound” to describe their adhesive layer. Nobody seemed to be drawing the right conclusion from sellers’ attempts to hide the fact that they were selling asphalt. For several years the argument was about durability. Asphalt had an unhappy tendency to melt or fall off. At the time, there were no reports of butyl adhesive failure – that had to wait a few years until one seller decided to re-purpose some low quality butyl roofing material. I spent a lot of time trying to figure out why this was happening. All of these materials are asphalt with some sort of rubber added to increase heat tolerance. The generally accepted melting point for these compounds is 180°F. That seemed high enough for use in a vehicle, so what was going on? Our perception of the heat these products are subjected to was wrong. We thought in terms of air temperature inside the vehicle, maybe 140°F-150°F? It turns out things are very different at the sheet metal. Park a car in the sun during the summer, south of the Mason-Dixon line and you can easily get to 180°F+. That explains immediate failures in hot climates. An insidious part of this problem is that many failures were reported during the second or third summer, many in fairly mild regions. The explanation was pretty simple. The rubber added to asphalt deteriorates over time when exposed to temperatures much lower than those required to melt the fresh material. As the rubber deteriorates, the melting temperature drops. Suddenly it doesn’t take much heat anymore. The durability question has been answered to my satisfaction. Many high profile asphalt devotees, including some who went to almost insane extremes to install the material “properly” have had their installations fail over the years. A few of the brave ones have come forward and made their results public. The pennies vs. dollars argument still nags. What if you plan to junk your vehicle after a few years (worse, plan to trade it in and don’t care what problem you are passing on)? Is asphalt a reasonable choice when durability isn’t a factor? Nope. There are two main reasons people believe they can substitute asphalt roofing materials for CLDs: They look alike – shiny on one side, black and gooey on the other. They don’t understand how a constrained layer vibration damper works. See: Caddy Shack, swimming pool scene for all you need to know about point 1. Point 2 needs more consideration. I used to believe that vibration dampers work by adding mass to a panel and lowering its resonant frequency below the audible range. This is completely wrong. They work through a fairly complex sequence of events that occur in the adhesive layer and between the adhesive layer and the constraining layer and substrate. I won’t go into the details here, please see: Vibration Damping By Ahid D. Nashif, David I. G. Jones, John Phillips Henderson The important point is that everything depends on the material property viscoelasticity. Basically this describes something that can be deformed and will then return to its original shape more slowly than it was deformed. The strains created during these events account for the conversion of vibration to heat that we’ve all heard about. Butyl adhesives formulated for vibration damping are viscoelastic. Asphalt isn’t – it doesn’t need to be to seal a roof. Asphalt adds mass to a panel. It may stiffen the panel, but since stiffening raises resonant frequency, the two mechanisms are offsetting and reduce effectiveness even further. Those who claim to have used it and had good results aren’t giving you the full picture. These claims can be better stated as: I used asphalt. It was better than nothing. I haven’t used a proper purpose designed vibration damper so I have no basis for comparison. It hasn’t failed yet. Sometimes the endorsement is explicitly stated: I used asphalt and it hasn’t fallen off. Not falling off is a pathetically low standard of performance. Testing I’ve done has convinced me that it takes between 6 and 10 times as much asphalt to achieve something approaching the same result you will get with a real vibration damper. This puts the pennies/dollars question on its head. Add the durability concerns and the huge amount of extra work required and the answer is pretty obvious. I’m sure some will want to argue the points I’ve made here. If that’s you, please stay away from “I used it and it worked for me”. That’s how we got into trouble in the first place and doesn’t make any more sense than concluding that cigarettes are good for you because your grandfather smoked a pack a day and lived to be 90. If you want to go there, please show us some evidence.

Wow! What kinda enclosure are they in! 151db on 600rms each is amazing! Seems like it should of did the 156 with rated rms (2250). Is that a wall setup or bandpass? Cant be a regular ol ported setup. Unless u really kno wtf ya doin. he doesn't know what he is doing.. The subs are installed IB ... Full o' fail!!! He has sum vids on youtube. The setup looks gud n loud. He has a T Top 2. He does a 156 and has a T Top 2?

Thanks Buddy! Rims are 20" XD Monsters and the tires are 35 x 12.5 Nitto Trail Grappler Well I am going to paint it after the first of the year, maybe march..........so it will be welded back up. Hows this for progress? LOL

This is a repost from Here, I thought it was quite important for people to realize this when they are posting. Definition of Objective and Subjective Objective is a statement that is completely unbiased. It is not touched by the speaker’s previous experiences or tastes. It is verifiable by looking up facts or performing mathematical calculations. Subjective is a statement that has been colored by the character of the speaker or writer. It often has a basis in reality, but reflects the perspective through with the speaker views reality. It cannot be verified using concrete facts and figures. When to Be Objective and Subjective Objective : it is important to be objective when you are making any kind of a rational decision. It might involve purchasing something or deciding which job offer to take. You should also be objective when you are reading, especially news sources. Being objective when you are meeting and having discussions with new people helps you to keep your concentration focused on your goal, rather than on any emotions your meeting might trigger. Subjective : can be used when nothing tangible is at stake. When you are watching a movie or reading a book for pleasure, being subjective and getting caught up in the world of the characters makes your experience more enjoyable. If you are discussing any type of art, you have to keep in mind that everyone’s opinions on a particular piece are subjective. Easy Ways to Remember Objective and Subjective Objective : sounds like the word object. You should be objective whenever you are discussing an object, something concrete that you can hold or touch. The facts that make up your objective statement should also be concrete, solid objects. Subjective : is just the opposite. You can’t point to subjective subjects. They are all in your head and your past experiences. Subjective opinions are ephemeral and subject to any number of factors that can range from facts to emotions. Examples of Objective and Subjective Objective : scientific facts are objective as are mathematical proofs; essentially anything that can be backed up with solid data. Subjective : opinions, interpretations, and any type of marketing presentation are all subjective. Summary: 1.Objective and subjective statements are used by speakers to get their points across. 2.Objective statements are facts that can be verified by third parties while subjective statements may or may not be entirely true as they are colored by the opinions of the speaker. 3.Objective statements are most commonly found in the hard sciences, whereas subjective statements are generally used to describe the arts.

Wow! What kinda enclosure are they in! 151db on 600rms each is amazing! Seems like it should of did the 156 with rated rms (2250). Is that a wall setup or bandpass? Cant be a regular ol ported setup. Unless u really kno wtf ya doin. he doesn't know what he is doing.. The subs are installed IB ... Full o' fail!!!

+1

Try to use a piece of paper with member name and SSA.com in a picture next to your item you are trying to sell

Thanks, fitting the 8" speakers in the door was a piece of cake, I have plenty of room. I have 8" pa mids in the doors right now. I'm going to swap them out with the Soundstream coax soon. They will be temporary as well, when I decide to start glassing, they will be replaced.

Grammar?

I would have moved this thread for you ... but ...

Nothing wrong with .5ohm per amp.