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Seems like the spam bots have gotten 'smarter'. I've seen a smaller forum literally flooded by spam and it made it impossible to be read. Whenever you see a spam post, please report it so we can take care of it. Thanks !

Yes.

Crush him with teh BTL, it can me done Lol you should recone the BTL to look like a funky pup Too bad I didn't get a dustcap when they were available I got some.

They are different beasts, but physics remain the same. Some people do things more because it gives them a warm, fuzzy feeling inside than any logical acoustic purpose. But, let's look at this a little more. First, we would need to determine the potential for standing waves within the enclosure. From what I could find the formula for determining the fundamental frequency for standing waves is; f = V/2d Where: f = Frequency V = velocity of sound d = dimension of the parallel walls His enclosure looks to be around 54" tall (based on the approximately 18" cutout on the baffle, it looks like the overall height is around 3x the size of the cutout, so we'll guesstimate 3 * 18 = 54). The velocity of sound is around 1130ft/sec, or 13560in/sec. Using the above equation, this would give us: f = 13560/(2*54) = 125hz So, the fundamental of the standing wave in that enclosure would be 125hz (there will be standing waves at the harmonics as well, but we'll ignore those for the moment since they'll be far enough outside of the bandwidth to not really matter). Where is the typical subwoofer crossed over? 60-80hz? With a fairly steep slope? With a 60hz lowpass and 24db/oct crossover, the output from the subwoofer itself would be attenuated by 24db before you would reach the standing wave. You would be well outside the operating bandwidth of the subwoofer, at 125hz the output from the main speakers should be dominating the response of the system. So that standing wave won't really be much of a problem to begin with because it will be well enough attenuated and outside of the bandwidth of the subwoofer . But let's say we do feel that the 125hz standing wave is a problem, maybe we plan to use the subwoofer up that high. We can't only worry about the standing wave itself....we also have to look at what is done to "fix" the standing wave problem if one exists. This guy felt that lining his enclosure with OCF (open cell foam) was a good solution to the problem. Now, the absorption coefficient of an open cell foam is directly related to it's thickness (among some other things). He doesn't state what the thickness of the OCF is....but the wood is 3/4", and the foam appears to be somewhere around twice as thick, so let's assume it's 1.5" OCF. What is the absorption coefficient of 1.5" OCF at 125hz? (absorption coefficient is how much energy is absorbed by the material). It's probably going to be ~ .1 or so, which means it's only absorbing 10% of the energy. 90% of the energy is still present. Pretty ineffective treatment, wouldn't you say? So let's say you have a really large subwoofer enclosure that has a standing wave right in your problem area, say 50hz (you would need to have two parallel enclosure walls approximately 11 feet apart to have a standing wave close to 50hz). You are not going to be able to throw some 1.5" or 2.5" OCF on the enclosure walls and call it a day. The absorption coefficient of that thickness OCF is going to be virtually zero at 50hz. The foam would need to be incredibly thick, and ideally spaced away several inches away from the enclosure walls, to begin to have a noticeable effect. Not something easily accomplished. So, moral of the story. Most people aren't going to experience problems with standing waves within the enclosure for subwoofers. If they do, then the solution shown in that link (relatively thin OCF) is not going to do much to solve the problem anyways. Polyfill has a different goal. The goal of the polyfill is to "trick" the enclosure into thinking the enclosure is slightly larger than the physical dimensions. It can work for this purpose. But the lining on the enclosure walls are not polyfill. For polyfill to work, you need to restrict the movement of the air within the enclosure. Polyfill is essentially pillow stuffing.

Go to this link and fill out a repair quote. Chris will get back to you, but don't forget it is Saturday. http://www.db-r.com/

There are an infinite amount of sub/amp combinations that will get loud. However, if your only goal is getting loud you may want to switch your focus from sub/amp combos to box design and placement in your vehicle. Granted, subs such as Btls and Level 5s can get very loud. But an ssd or level 3 in the right box can get louder than a btl or level 5 in the wrong box.