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Well it has been a bitter sweet day, the XCONs have a new owner. I helped the new owner load the box in and wire them up and as I watch the red X-Wagon leaving all I heard was the XCONs trying to break out. I know they wanted to stay, but with a tear in my I watch Austin smile and drive away. That poor van has no idea what it is in for.

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.

I'm guessing power cable ran straight from the battery to the HU with a 100 amp fuse in the fuse holder.

I just installed some Zcon 15s, so I have something to play with until I receive my order. My only fear is that I like them too much and want to keep them. I ordered them for a friend who is still planning her build. They freaking pound, it's scary. I can sit patiently I suppose, until she wants them back.

My order # Straight Up EVIL 666

I have doubts your current "prefab box" has correct port area and the also placement is not good for a trunk setup. I have no idea how a well built sealed box compared to your current box will sound. But I know that a well built ported box with correct port area and sub placement would be no comparison in loudness, sound quality is a personal preference. I know guys that swear by sealed until they hear a good ported setup and they never go back. The high or low QTS option on the subs and the space you will allow to be used should be taken into heavy consideration. Seems you need to think about it more, your "Max dimensions" dont seem to be max at all since your current box is way bigger, lol.

I think Aaron was suprised when he hear the DCONs on low power in person. I've heard them plenty on low power, just was surprised at the output and composure in that enclosure.

Forget the rear 6x9 speakers. You will not be able to hear them through your subs !!! That would leave you some more money for a decent component set for your fronts, and maybe some deadening product for the doors. You may like Skar, but after what I've read about this brand, I would not buy their products. But it's just my personnal opinion. Do what you want ! For the subs, try them in as many boxes you can ! If you already have a ported box for your, car try them in first. They will sound good in a sealed box, but they will also be louder in a ported one. I don't want to run sealed boxes again, since I know how to get well designed ported boxes now !

I'd say try different boxes for the 12s like both the subs and port facing back. A well designed ported box is better than a sealed. Are you joking about the skars being wonderful? Haha Wait, have you tried the subs in the box already? Or are you saying the re was like that? Try the Qs in the box you have and see how they are. That's the only way you'll know if it sounds good or not.

I'd do the 2 15s big jon has in a big box with your sundown 3k. That'd be loud!!!!

A picture from tonight, ready for some food!

thanks!!! i have something sorta bg planned for the audio....... 2 solo x's in a wall is in the werks!

They have Popeye's in Japan? Learn something new everyday

im going to cut my eyes our with a spoon now.

Time for some underhung sex