2004 Pilot Subwoofer Install MDF/Fiberglass

[Toy Civic]

Hello. My name is Craig Nelson.

I've been meaning to post these since I did this install last year. Been quite busy since then.

I retired from the U.S. Navy in Sep 2011. I then went to The Installer Institute, a 10 week mobile electronics school in Daytona Beach, FL. I'm currently in Laramie, WY. attending Wyotech. I've been into cars and high end audio since the early 90's.

While at The Installer Institute, I came up with this subwoofer enclosure design. This took me a few days since it was my first time doing an ultra stealth and advanced woofer enclosure like this. If you took your Pilot to a shop, this will take less than 2 days or about $600-$800 in materials and labor. The Alpine sub retails for $500, but can be had for less than $300.

If you are queasy about cutting the sheet metal behind the passenger side cargo area panel, then this is not for you. However, this is the BEST way to get proper sound quality while keeping the cargo area space at 100%. The whole factory cavity cannot be sealed due to the sheet metal design and construction from the assembly line. So any attempt at mounting a sub using the factory sheet metal and the 10 inch hole will cause excessive resonances and a flimsy mouting baffle despite any MDF rings. It will ONLY be a free air design no matter how much you try to dynamat or seal anything.

The woofer is an Alpine Type R SWR-T10 shallow sub. The box is very close to 0.42 cubic feet sealed. The amp is an Alpine PDX-5 feeding 300 watts RMS to the sub. The sound quality is superb. My max SPL is 127dB at 45 hertz. the box is filled with polyfill. This will play accurately down to 25 hertz. By the way, all Alpine PDX amps fit VERY nicely under the passenger seat with minimal work.
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It doesn't matter what kind of subwoofer enclosure you have. The internal acoustics in all 2003-2008 Pilots bring a MASSIVE and NARROW dB spike centered at 45 hertz. I tested this bass transfer function using an Audiocontrol SA-3055 RTA/SPL meter, a test CD, a 100 watt amp, and a JBL 8 inch woofer in a sealed enclosure. Please review my bass transfer chart picture.

In order to get a reasonable amount of smooth bass frequency response, your system must at least have an EQ cut control centered in the 40 to 50 hertz range..........to get 25-40 and 60-80 hertz to have similar bass response. Your system should also have some kind of subwoofer level control. The problem is, most lower end head units don't have EQ controls towards 40 hertz. Most are at 63 hertz. If so, you can boost 63 hertz to get some smoothness, but you end up with diminshed output between 25 to 40 hertz.

My low pass crossover is set at 63 hertz at 18 db per octave. The high pass crossover for the front stage is set at 63 hertz at 18db per octave. The result is a seamless transition from sub to midbass and an EXCELLENT front stage bass presence above 50 hertz. My front stage components are high end Polk Audio SR6500 units.

I have a total of 59 pictures of the sub enclosure build, but this site has limits to the number of pics uploaded. If you want more info, PM me with an e-mail address and I will give more details.

[hp2004]

Very good information here, Sir. Great job on the produced enclosure.

[DMG]

Nice write-up and a clean install.

[THE215]

Nice glass work man!