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I had a sample tile of SDS CLD laying around that Don had sent me a long time ago that I hadn't figured out a use for yet. So I decided what the heck, I'll throw it in the kickpanels! I originally hadn't planned on putting the SDS in the kicks as I actually forgot I had that tile laying around....it was a last minute addition. I cut the tile into quarters and laid it on the larger areas to hopefully help dampen some resonances. Kicks getting a little SDS'ification: After that I proceeded on to the time honored SQ tradition of piling on some non-hardening modeling clay (NHMC). The idea being to add mass to the structure to shift and reduce the resonances. How well does it work? I really have no idea! How do you like that for an answer? Seriously though, I've not seen any quantitative data on this method, and I don't have the equipment to conduct such a test. But a cursory investigation of the kicks pre- and post-NHMC revels that the kickpanels are significantly heavier after adding the NHMC (which is good, knowing that I need a 4x increase in mass to lower Fs one octave....the heavier the better), and with the 'ole knock test the kickpanel with NMHC sounds much less resonant and "hollow" than the kickpanel without NHMC. So, subjectively it appears it should help some. I've used it before but didn't really spend any time trying to compare with and without differences. And for $10 it isn't that expensive. I have something like 2lbs of clay per kick, which doesn't sound like a lot but really the difference is weight is extremely noticeable. Plus, it adds all kinds of pretty colors! I didn't add much to the backside of the kickpanel because clearance is tight, and the form is cylindrical which will be stronger and less prone to resonance than the large flat areas. Oh, and since I didn't mention it before I also chamfered the rear of the mounting ring for the midbass since the .75" MDF is approximately the same depth as the side openings in the midbass' basket (which is the only escape path for air on these midbass) to help improve airflow. And that's where they sit Before I put the speakers in I'll also fill each kick w/ polyfill. Other than that, it's just waiting for the weekend and some daylight so I can get them installed!

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.

Cool, go ahead and post it here. This is SSA.

After you get the recone.. you should set your gain correctly..

Depends on your goals, processing, and what your ears require. They make some decent stuff, some garbage, and some in between.

Goldwood speakers are a fairly generic brand. I've used them to repair/replace some drivers in house speakers for myself and a few friends and they do a pretty decent job. I'm not sure how much abuse they can take, and they're not the best at accurate music reproduction but they're not half bad either. If I was going to look into building a set for my vehicle, I'd look into a different brand though. Madisound has a brand named Silver Flute which has peaked my interest, especially after SMGREEN20 has said they're comparable to the Hybrid Audio L6 mids which says alot to me about the quality of their musical reproduction and they're priced very similarly to the Goldwood stuff at the Madisound store.

No experience but they are price friendly. May want to search a little on Madisound as well as Parts Express for raw drivers.

Vance Dickason demonstrated that larger port area results in better port linearity, which equates to deebeez

Clipping is when the wave becomes squared off when you over-drive an amplifier -- it has a higher average power and therefore delivers and consumes more energy (can also blow speakers due to the higher average power).