Xoutpost.com - JL Audio Stealthboxes in E46 M3

I think the JL Audio Steathboxes were not cheap....I think they were about $300 for the pair (two 8" JL Audio subs in their special surround). The JL Audio 250/1 AMP was about $200-$250....but now, they have newer different amps.

I disconnected the OEM 6x9 Sub Amp for H/K system and wired the rear speaker signals to the 6x9s and tapped into the rear speaker wires for the source for the JL Audio subs. The JL Audio 250/1 amp has a built-in crossover and I set it around 60-70 Hz with a more steeper slope (24 dB slope) and minimal bass boost.....I don't remember the settings, but you can play with it to your liking.

The JL Audio stealthboxes really don't take too much room. The big removal sub box will take some space, but because the E36 & E46 trunks are well sealed, if you use the box, you'll should cut a hole somewhere on the rear deck to allow sound from the trunk to get into the cabin for better effect. The JL Audio stealths fit right under where the rear woofers normally go....you just toss those out and using the 6x9 as the rear fill speakers, it works fine. The tweeters are intact at the above the left & right rear side armrests.

I think for an 8" sub and minimal trunk space, it works out well. Granted, it works like a free-air sub and using the trunk as the box, but for what it is, it is pretty darn good. However, I do admit, my JL Audio sub in a sealed box in the stock OEM sub location sounds better.