BMWM5

Beware that the trunk on the coupes are fairly well insulated from the cabin. Because of this, bass emanating from the trunk trying to get into the cabin will effectively to so via/through your rear speakers woofer cones. You can verify this by unplugging the rear speakers, running some strong bass passages, and observe the motion of the rear speakers woofer cone without it plugged in. To combat this you will need to build a small sealed box for the rear speakers. This will allow the rear speakers woofer to have its own acoustic cavity and disallow the subwoofer from trying to breath through it. This may also reduce your subs output into the cabin because you just took away the easiest path from the trunk to the cabin. To fix this you will need to "open" the rear deck up. You can leave the carpet with no consequence but metal and the hard cardboard from the parcel shelf needs to be removed. Another option is a "Bandpass" type box with the output port exiting into the cabin via a 3-6" port. Yet another is the "freeair" or "infinite baffle" type, this is what I used in my coupe with 4-10" JL Audio 10W4IB's. it does require a lot of work though. For this configuration to work effectively, the front side of the woofer needs to be completely isolated from the rear. As I said earlier, "the coupes are fairly well insulated from the cabin", fairly is not enough for proper efficiency. I found the seatbelt mechanism to be the worst offender. The thin non-rigid metal in front of the gas tank was a problem too. I eliminated both by building the baffle all the way to the floor of the trunk, isolating the air space from the cabin with 0.75" - 1.5" MDF fiberboard. I took a lot of time but the results were outstanding. FYI I mounted the 4 10" subs upside down so the basket and magnet structure resided in the void of the parcel shelf and because of the thick baffle I built, there was no protrusion past the natural curves of the shelf, STEATH!! I of course kept all of my trunk space too.

Food for thought,

Brian

BMWM5

I'm terrible at typing and thus don't post often. I don't mind sharing but do need to know if it's being read and if i'm helping anyone.

Brian

Econobox!

Stereo stuff is mainly a mystery to me--most of my cars have the radio removed as soon as I get them. Your post seems easy enough to follow though. I'm sure someone more in-tune (har har) with stereo stuff would get more out of it.

Blake@NWAutoSalon

I read it as well, but my lack of interest + ADD, ADHD kicked in...

JeromeS.

It makes sense, thats probably why it sounds better. Most people (including myself) wouldnt go that far to make a car system sound better. How long did it take to do it?

- GT Style -

Nice thorough write up. Pics?

StormChaser404

Go away...troll...

- GT Style -

Unfortunately it's not that easy. He just bought a 4kq.

1984cgtturbo

The stock rear speaker holes are simply covered by grilles to allow the bass in my trunk to pass through without a problem.

J.

- GT Style -

Pics of the 6x9 enclosure setup?