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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.

Here's the problem boys, everyone else, who has nothing at all to do with this, keeps posting shit. If you're not the OP, or DC, don't reply. Simple as that.

//lazy entry. ///has boobs.

Quoting the most ridiculous prices for effect! http://www.soundsolutionsaudio.com/store/categories/Speakers/Bravox-Audio/

I'd vote for that single DCON. You'd be very surprised what that little woofer can do in the space you're working with. Not to mention, the money you save on a single woofer can be put towards your amplifier budget to get something with some serious quality.

I had a Sony CDX-C910 I was going to use in this install. Unfortunately it died when I installed it. I heard it power up, but had no display and the face would not go up or down. I used an Alpine CDA-7894, but it never sounded quite right, plus I got a good price on the Kenwood (thanks Carmil and Car-Fi!) and since I wanted Bluetooth I went with it. The truck was a learning tool. I'll go all out on the Altima when I do it, but right now funds are tight and I just don't have the money to do another one right now. I would like to find a Pioneer 880, Alpine 7909, Clarion DRZ-9255 or something similar in quality, but it would have to be in a price range I can afford. I still look on feesbay and maybe one day I'll get lucky and find something in the range I'm looking for. For now, this one does everything I want and more. I don't use any time alignment, DSP, or anything like that. I use the front outputs only and run them into the PA-II and from there to the XO-3 and then to the amps. Pretty simple setup. A 7909 or similar would fit the bill nicely, but I haven't had much luck locating one in a price that's not going to get me killed by my girlfriend. I've been informed her car is next since I've done two of mine AND her son's, and her's is still stock! Keep momma happy and she keeps me happy! Jimmy, are you going to finals? I would love to show you the truck and why I did things the way I did. I find it difficult to explain over a forum the "why" part of why I do things, it's just easier for me to show someone and let them decide for themselves if it worked or not. There is no trickery involved with any of our (mine, John's, Randle's, TJ's, Herman's or Ray's) installs, just solid equipment, maximization of the environment (ie, sound damping / proofing), good speaker aiming and lots of listening and experimenting to see what works in each of our vehicles. Unfortunately, (or fortunately in my case, thanks John!!) most of us have trucks except for Ray, which is why we are trying to get Kim's HHR and my Altima going for next year. I look forward to seeing you at a show someday, as I would like to listen to your vehicle as well. I know you like Linear Power, or at least you seemed to on DIYMA. I can't remember what you ran in your personal vehicle, but I'm sure it sounds great.

I'm going to shoot some really nice pics of this thing to post on our website tomorrow Andrew

x2 or your amps are set correctly causing them to turn the excess power that its trying to make into heat. How are your amps set, whats the pre-out voltage of your headunit, how high are your gain settings? My amps are already hot when I get in the car and get pretty hot depending how hard im pushing them and how long, just like any electronic piece of equipment after use its temperature will rise subtantially and if the air around it is not cool then it will just add to it. If worried about change listening habits or turn the gains down some. Even though I know you guys barely have winters but wait till the temperature cools and if you keep your setting exactly the same your amps will be way cooler.

As was stated before, both amps are great and will do well for getting good sound from your system. The preamp section in the DPS500 is a little better than the 2.2HV. It has slightly better channel seperation and slightly better S/N ratio. I believe this is why my soundstage got a little wider and deeper, or at least I assume so. That and also being able to push the seat farther back helped as well. When my seat contacts the amp, that's as far as I can go in my cab. With the 2.2HV, my seat would stop waaaay before it does now. By getting another 1/4" of room because of the shorter height, AND with the different profile of the heatsink AND with the amp being shorter in length, I was able to mount the amp lower on the amp rack which allowed me to push the seat farther back. All of that COMBINED allowed me to make a better soundstage and get the listener in the "sweet spot" so to speak. I believe those COMBINED things is what the judge heard and commented on. The 2.2HV is still one of the best amps out there in my opinion for driving a front stage or subwoofers cleanly. Is it the "best" amp there is? Who knows? Depends on who you ask. I like it and I like my DPS500 the same. The DPS amp allows me to put the seat in a better listening position so I can be more in the sweet spot and have better imaging and staging. John has never had the 2.2HV in his system so he can't compare the amps directly. When he and Ray got to talking about the amps, I think one of them made comment on the profile of the amp being shorter and we decided to try it to see what would happen. That's why they were changed. Nothing more to read into it than that. If you have any more questions about the amps, I am more than happy to try to answer them for you.

Which model? The CS60B model.... I love these.... They weren't on earlier today, right???? I think I am going nutz here ... Didn't see them in the store, only the yellow models... I asked about these and the CS60D, Denim just added them back on the website, check the links above...

So your plan was instead to defraud your potential customers by posting pictures of enclosures you didn't build? You obviously have a camera.....you didn't think it was a better plan to just wait to start a thread until you had pictures of better built enclosures that were your own work? I don't like this thread at all. For one, you're trying to generate personal income from this forum without any benefit to the forum itself by means of advertising, becoming a supporting vendor with your own subforum....hell, you're not even a supporting member. And to top it off, your initial business plan was to attempt to defraud everyone by claiming other peoples work as your own in order to generate business. Thread closed. I really don't see the point in allowing this to continue any further.

Umm buddy, Trevor Komat built that enclosure.