78 280Z LS3 Project in Gen III & IV Chevy V8Z Tech Board Posted June 13 Something else I noticed as I started driving the car is that I could barely hear the 6x9 speakers I installed behind the seats. It seems like the sound was muffled due to the seats being in front of the speakers. The other issue is that the motor in this car is fairly loud and the stereo needs to compensate for that sound so I had to turn it up and at some level the speakers would get a bit distorted due to all the bass they needed to put out. My system is a JL Audio 6 channel 600 watt amp which runs four 6x9 JL Audio 3 way speakers, two are mounted on a panel by the taillights and the other 2 behind the seats. I also have two 6 ½” JL Audio speakers on the door panels. I spoke with the JL Audio support team and explained what components I was using as well as the car they were in and the locations of the speakers. They mentioned that I should replace the two 6x9’s behind the seats with a subwoofer and that would help tremendously since I would be able to run the Low Pass signals through the subwoofer and the High Pass signals through the remaining 4 speakers instead of high and low pass signals through all the speakers which is what’s happening now. That would give crisper highs, deeper bass without distorting the speakers. Since I did not want to build a subwoofer box due to the limited space I have in this car they suggested running two 6 ½” subwoofers in place of the 6x9’s behind the seats. So another project begins. I have to say JL Audio customer support is incredible, they calculated how much space I needed for each subwoofers and I built the enclosure to their recommednations. I removed the 6x9’s behind the seat and made wood panels to enclose each area. I put some L brackets on the wood panels and bolted them in place. Then used tons of silicone to ensure it was completely sealed. I had already put Dynomat in those areas so that helps eliminate the tin sound. Then I built a wood face panel to bolt the subwoofers in place since the holes I had for the 6x9’s were too big. I used foam behind the panel in order to eliminate any rattling and bolted the panel in place. Fitted everything and re-carpeted the panel. The sound difference is incredible, it blows me away how much bass comes out of these little subwoofers. I don’t listen to rap all the time so I don’t need a rolling boom box but certain songs require clear bass and these speakers deliver. Below are some before and after pictures as well as part of the process.