m444

Excellant write up, thanks.

One can find the polarity differences of the speakers with a 1.5V battery. Just assume the postive terminal of the battery is the + terminal on the speaker. With a momentary connection accross the speaker terminals the cone should move out toward you. Do the same for old and new speaker, which will tell you of any polarity differences. If they move the same direction, under the same condition, then polarity is the same. Of course for a subwoofer, due to cancellation of bass, the correct polarity will sound better (more bass).

The Kicker 10C108 speaker I pointed out before, is rated for Free Air operation. Here is a comparison to the JL speaker similar specs, except for lower compliance and efficiency, so the JL woofer should work. These are never going to be optimum for sound, but they do not require an extra amp or a box.

sworksone

Excellent write up. I'm planning on doing the exact same installation next weekend if the sub and dynamat arrive in time. Your write up will make things much easier. Also glad to hear you're so happy with the results.

koobah

The Kicker does have a higher sensitivity, plus, per manufacturer, it is suitable for free-air installations. Here are more detailed specs on both subs:

helix139

The JL does have higher power handling and better surround material that should last longer. Anyone know what the stock B&O amp actually puts out sustainably? Should be easy enough for anyone with a DMM and access to some test tones to find out. put in the test tones, crank the volume to max, and use the DMM on the sub wiring to find the sustained voltage and amperage and use ohm's law.

billyg

Awesome write up! I think I need to do this sooner than later. Now which sub to grab, hmmmm....

NWS4Guy

B&O is 550W max, though unknown how much of that goes to the sub, I would hope at least a good 100-150, and it is an 8ohm system anyway.

redrocker55

OK...I think I'm getting the feeling I might need to move to Seattle or something...seems like there's lots of cool S4 action going on in the northwest and in St Louis...........not so much!!!

Great DYI!!! Love the color of that S4 too!!!

NWS4Guy

I think you would fit in, and it's a really great area too

m444

koobah,

Not sure where you pulled the Kicker specification from. The one I posted came from the Kicker manual, which can be found here;

http://kicker.com/Product_Manuals/93/105

Here is a snapshot from the Kicker manual;

m444

Also, the JL manual says it is 300W, not 600W.

http://mobile.jlaudio.com/pdfs/8551.pdf

The snapshot of the JL specs from manual below;