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So I was an idiot the other day and didn't have my CF card in my camera. So, the photos of the contruction of these pieces is lost forever. But, here are some highlights of the current progress. I've actually made a bit more progress today, but no pictures yet. I should have pictures of the nearly completed box tomorrow or the next day. It depends on whether I assemble it completely before doing the epoxy coating.

Today I'll be spending most of my time building the subwoofer box. The plan is to have it essentially completed so that it can be epoxy coated and allowed to cure over night. Hopefully, I'll also have time to roll on a coat of Spectrum as well. Either way, there should be some interesting progress made today.

I've made it through one gallon of Spectrum and covered almost everything with 2-3 coats. I only have one coat on the outer skin behind the speakers. I've been brushing it on and I plan to roll on the last gallon to give it a nice smooth texture. Here's a few pictures. As usual, more are available in my Picassa Web Album. I've also made some more progress on the subwoofer box. The frame that fits in the back seat wells is almost complete. I hope to have most of the box assembled tomorrow and ready for epoxy painting.

I've successfully installed 116 square feet of Damplifier Pro. Whoo hoo! Now I'm waiting on UPS to show up with my Spectrum (liquid deadener) and spray adhesive the Overkill (closed-cell foam sound absorber). In the mean time, it's back to working on the subwoofer box. I should be able to make good progress on that today as well.

I'm almost through with 80 square feet of Damplifier Pro. I have another 36 that just arrived the other day that should be enough to finish up the back. I don't think it's going to be enough to do the front doors, so I'm going to probably have to wait to do the front until another time. That's not too big of a deal, but disappointing anyway. But, it is also the most convenient part to put off until a later time since the doors are discreet components. I have also started on the subwoofer box. I've built in brackets that tie into the original seatbelt mounting points that the rest of the box will tie down to. I've also simplified my design slightly from what I posted ealier. The stepping of the speakers to line up the cones isn't really necessary in a bandpass box or for subs in general I would imagine. Aligning the cones is simply used to change the directionality of the concentrated output. Since low frequencies are non-directional, and everything is co...

No posts in a few days, just applying more and more Damplifier. I've bought another 40 square feet which should be enough to properly finish the rear half of the car and do the front doors. In addition, upon numerous recommendations I found online, I purchased 2 gallons of Spectrum, Second Skin's liquid deadener. Apparently the secret technique to getting the best results is: Average 2 layers of Damplifier Pro on the the whole car. Paint on a layer of liquid deadener (either Spectrum, or Spectrum Firewall). Add a layer of Overkill (a closed cell, neoprene foam). In that order. So, in addition, I got 60 square feet of the Overkill to finish of the rear half of the car. The liquid deadener is almost a must over top of the Damplifier matting. The sticky butyl stuff on the back has a tendency to squish out between the seams and make a real sticky mess of anything that comes in contact with it. The liquid Spectrum should provide a nice, clean surface for everything to be laid down o...

Here's my subwoofer box design. As I mentioned previously, I've gone with a push-pull design to reduce the size of the box. I'm also using two slot ports. The whole thing will be built out of 3/4" MDF and then finished with carpeting. The drawing doesn't include the contours to make it fit in the back seat wells. I'm going to have to cut that to fit. The volume there won't be exact, but after playing with the numbers and looking at the frequency response curves, I think it will be within my threshold of satisfaction.

Still going... I'm not quite half-way through the 80 square feet I bought. I took some pictures and I'll put them up later. I learned a couple more things today. You get what you pay for when you're buying ratchet sets. That $10 set at Advanced Auto sure looks nice though. The matting is pretty flexible, but bubbles are a real pain. Be sure to squeeze as much air out as possible by rolling it on and pressing it down as you peel back the paper. Other than that, I've learned it is a time consuming and laborious process. I sure hope it's worth it!

So, there are too many pictures to post them all here in the blog. I'll start including relavent pictures in entries from now on. However, all the pictures taken will be available at http://picasaweb.google.com/damonkohler/cougarproject2006/ . Here's a quick photo timeline of the progress so far: Before-shot with the sub box in the back. Shots of removing the interior. After-shot of stripped interior. Measuring the volume of the seat wells to do my subwoofer box calculations.

I've gone through two sheets of Damplifier Pro so far, and this is what I've learned: 2" strips work great for hard spots. Don't bother with more complicated shapes. The roller takes a beating. I'm really glad I paid extra for the heavy-duty rubber one. The sticky stuff is messy. Wear old clothes. (Doh!) Two sheets has gotten me through a single layer on one back seat well and 75% of one of wheel well. I have 38 more sheets to go. The plan is to first cover the rear half of the car. That is, everything from the edge of the back seat to the trunk but not including the roof. I'll be putting at least two layers in the place where my subwoofer box will go, on the wheel wells, and on the inner-skin where my rear speakers are. I'm trying to come up with something to fill the huge void between the inner- and outer-skin in the back. I'm considering corrugated mattress padding. It's worked in the past...

Everything arrived today and I'm getting ready to start installing. The first step is going to be cleaning and preping the surface for the Damplifier Pro installation. I've been doing some research on this and on what the problem areas are. Here's the site that made me decide to go with Second Skin's Damplifier Pro: http://www.sounddeadenershowdown.com/ It has some great information and experimentation plus photos to back it up. I picked up a heavy-duty rubber roller from Crutchfield when I ordered my stuff from them. That should come in handy while applying the Damplifier Pro. Even though their product doesn't hold up as well as Second Skin's, Elemental Designs has some nice information on where to apply deadening material. http://www.edesignaudio.com/product.php?cid=10&pid=25&tab=Apps&cur=USD I'm in contact with Anthony, the owner of Second Skin, and I'm waiting for his recommendations on surface preping and application areas. It's very...

I've decided to set up a push-pull or isobaric box in order to reduce the size requirements. Doing so actually reduced the size by almost too much! And, in addition, I've had to go to a 2-chamber bandpass arangment since I don't know how a partially isobaric configuration would work (i.e. where only the vented chamber is isobaric) and I don't like the other options for 3-chamber isobaric (typical requires 4 drivers).

Designing the box has been a very difficult problem. The math isn't complicated, and is easily done with a spread sheet, but unfortunately I can't seem to make the box as small as I'd like to. This, of course, is because I'm building a bandpass box. But, I'm more willing to compromise on the size of the box than I am to compromise on the type. Building a bandpass box means that I can keep my speakers enclosed and protected. I hope to make the box look inconspicuous and easy to pack stuff on top of. Having two exposed 10" woofers doesn't accomplish either of those goals very well. So, I'll be using a 3-chamber bandpass with 2 sealed sections and 1 vented section. I'll have 4 slot ports on my vented section. Here are my calculations: Box Calculations for Fl Vas 101.14 l Fs 30.5 Hz Qts 0.445 S 0.7 b 0.7206 Fl 42 Hz Fl' 0.6127868852459 Fh 91.3894382022472 Hz Qbp 0.90392587983616 Fb 61.954470...

Project Overview Second Skin, Damplifier Pro Alpine CD headunit 4 x Kenwood 50W 6" x 8" component speakers (dome tweeters) with foam baffles Alpine 4-channel x 40W amplifier 2 x 10" Pioneer 350W subwoofers Rockford Fosgate 2-channel x 90W amplifier Custom subwoofer box The goal of this project is to improve my car stereo while allowing for future upgrades and increasing the cargo room in my car. To do this, I've removed the back seat and the large bandpass subwoofer box I had previously installed. In their place, I'll be building a custom bandpass box into the back seat well that will, hopefully, be almost flush with the trunk (within a few inches anyway). Future Upgrades I want to eventually complete some upgrades to the new system, so I'm building it with these goals in mind: Battery relocation 2 x Alpine 220W mono-amplifiers to power the subwoofers Touch-screen GPS headunit Status I have so far gutted the rear interior of the car. Next I'll be preparin...