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Hey all!

So, a few months ago, I posted basic questions about swapping the Bose system and CD24.

Thanks to everyone who commented, and to jeffbrig whose tutorial really helped shave time off the installation.

Sorry, but there are no pics as jeffbrig really covered everything, and because the Redundant Department Of Internet Redundancy is an office that should be avoided at all costs...well, you get it :)

I'll list out materials and then comment about the results.


JBL Stadium 6 1/2" component set, with optional midrange driver.
Tang Band W5-1138SMF 5-1/4" subwoofer
Morel MPS 4.400
Kenwood DNX994S stereo
CAI Store premium Porsche 997/987 radio dash kit
Bose wiring harness adapter from autoware302 off eBay
Kenwood DRV-N520
Miscellaneous infrared rear licence plate cam
Lots of wire
More patience than wire


The goal of the installation was to make it as seamless as possible, that is with as little cutting or parsing of the car as possible.

I used the sub out and the front out of the Kenwood. The tiny speakers in the Bose subwoofer remained in place, just not used. They do add a little to the sound with the stock Bose, but the cabin is small enough that they aren't missed with the new kit.

Give yourself time to do the installation. I've installed stereos in every car I've owned...well, except one...and this was easily the winner for the peculiar angle/tight fit of wire contest. And it was an education - Porsche really does not cut corners in the engineering department.

There are a lot of comments on the forum about a "hidden crossover" between the mids and the tweets with the Bose system for this generation. There isn't one. There is, however, a filter capacitor soldered to the stock tweeters. This serves to mitigate the low frequencies sent to the speaker. It's a tiny electrolytic cap on the underside. No fancy orange drop cap from an ancient electric guitar or magic audiophile paper-and-oil for a tube amp, just a basic cap. The wiring does, however send the same signal to both mids and tweets, but that has already been well established, so new wiring is certainly mandatory.

JBL speakers tend to be shrill. Mistaken logic lead me to believe that going with the Stadiums would produce a better tweeter, but no, it does not. The tweeter is the same as the component set one can get from the local big box. Adding the optional midrange for the stadiums made the components lean even heavier toward high frequencies. Use of the onboard equalizer in the Kenwood was necessary to tame it down. Frankly, they sound fine after working with it, but they need to be dialed in. The space of the cabin probably accentuates the highs as it is tiny.

The JBL midrange set came with brackets that fit in the door well, except the screw holes needed to be redrilled closer to the speaker opening by approx 2mm per side.

Further, the JBL crossovers are poorly designed. If the screw comes out of the strip for the leads, the washer will fall into the plastic case. This necessitates opening the case to retrieve it...and the sides are glued together. The case actually breaks when opened, so have some superglue handy if the washer goes missing.

Because the the JBLs are shrill, and even more unbalanced with the optional midrange, my advice is to go a different route if you can afford to. If you can't, then they'll do, but be prepared for adjusting the sound with the head unit.

The Tang Band 5 1/4" subs fit tightly in the space. There is lots of clearance for excursion, but the magnet hits the back of the enclosure. Not enough to make it bulge or deform, but it is certainly "well fit."

The sound of the 5 1/4" replacements is pretty good. It's not earthshaking like a 10 or 12, but with proper adjustment of the amp and stereo, a balanced sound can be found. Personally, I think that bass is certainly not underrepresented with this setup, but don't expect to compete with your neighbor's kid and the Kickers in his trunk. They are a definite upgrade over whatever Bose attempted to use.

Overall, with proper adjustments, this sounds fuller or more robust than the Bose system. Eventually I'll replace the JBLs with something more balanced, but more expensive.

Good luck, everyone!
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