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Old 02-14-2005, 10:24 AM
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Kewl X5 Kewl X5 is offline
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Join Date: Apr 2002
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For the E46 3-series, the JL Audio Stealthbox are about $400-450, the JL Audio 250/1 amp is about $300....You could probably do the install yourself, but it will probably cost about $200 for the install. You can go to and look up stealthbox for more info...they have PDF files you can download.

The 6x9s in the E46s are NOT two-way...basically a great mid-bass driver....BMW/HK decided to make those as "subs". The tweeters for the rear in the E46 coupes are in the rear side panels....above the rear side armrest. In the 3-series sedan, the 6x9 are on the far back rear corner (look in your trunk), but I don't remember where the mid-bass and the tweeters are, but they are separates on the rear last I remembered.

So, yes, I took the signal that originally was going to the 5" mid-bass driver and instead sent it to the 6x9s and also use that same signal to tap into and using a Peripheral SuperVendetta Hi-Lo converter to convert it to a low-level signal for the 250/1 amp. To answer your question, I adjusted the amp's crossover to blend in the subwoofer. I did it by ear.

This is by far the nicest upgrade without taking too much trunk space.

Ask Technic or I for more info.

Originally Posted by jetstream23
Nice! So to summarize, you've added the JL Audio 250W Amp and 2 JL 8" subs which are mounted under the rear deck where the 5" stock speakers once were? If you don't mind, can you give a ballpark total cost on this for equipment and install? Are we talking $1,000? $1,500? etc.

Thanks. It looks great and I'm sure it sounds even better.

EDIT: One more question...You're now sending the signal that was previously going to the 5" mid-bass drivers to the 6x9's. Are those 6x9's two-way speakers? Also, is the signal that's being sent the same midrange signal (say above 60Hz, below 2000kHz) from the HK amp?
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