A friend of mine owns a chain of car audio places, and he is advising me on installing a portable sub woofer under the front seat with my JBL 10 speaker system. He talked to a audio engineer who said that this system is quite proprietary, and the JBL digital HU is extremely sensative to adding things like an additional subwoofer.

Has anyone added another subwoofer to this system by coming off the front speaker leads? If so, how was it done?

He said if it was going to be done, it had to be tapped into the exisiting rear sub woofer/amp in some way. I hate to think of doing this, as I know what a pain getting to the panel where the existing one is.

My last car had a bose system with a separate amp in the trunk.

I tapped the pre-amp output from the head unit (at the amp) with an audio interconnect (RCA) cable. Cut one end of the cable, soldered to the amp input wires. Input the cable directly to an aftermarket amp for the sub.

The bose headunit only output 0.5 volts. But it was more the enough to drive my amp.


You can convert the font speaker input to pre-amp level with a Line Output Converter LOC.

But a signal before the JBL amps would be better, avoid any sound processing or filtering.


Car audio places won't tap the headunit output because of the liability involved. Using a LOC is easy and safe, but not the best quality. If I had the JBL system, I would try to tap the headunit pre-amp signal.

nah, Car audio places are able to tap the audio wires, with no problem, however it's just not as clear as having a new headunit with dedicated RCA's. The have a better filter on them. You can tap it into your dedicated subwoofer outputs, however it just wouldn't sound as good as a clean completely replaced system.

I'm having the same issue right now, I'm just saving up and paying stuff off to get ready to put a whole renovated system into my truck.

From what my friend is saying, this is one of the biggest challenges in the aftermarket car audio biz. Manufacturers are making systems highly proprietary to shut out the aftermarket guys. He said this JBL 10 speaker is a perfect example of this, as it is quite sophisticated to upgrade and/or modify.

Maybe I should think like you & save up to replace the whole system - or just leave well-enough alone. (One thing, if I buy a 100k mile warranty, at least the factory system will be covered.)

leave it alone?! :-O you insane? hehehehe... you haven't caught the mod bug enough yet. but yep. The 4runner comes with a dash that thank god.. we can still install a headunit in... the new volvo's... I tried to work on one.. wasn't able to... the new mazda's... I can't either.. the new subaru's... can't either... really killing me....

but I plan to keep my beautiful 4runner for a long time!

I got my whole system planned out,

Gonna cost me 2800 to get just the speakers, amps, headunit, sub and all the dynomat all together!

It is not impossible, but I tried two shops and decide to do it myself.

It is easier for shops to sell LOCs or a new headunit and guarantee their work.

I'd never chop up rca's and splice them in. Selling the LOC is much more better. I've put them onto monsoon systems with no problem.


Best Buy is only allowed to sell the LOC if you wanted to add a sub to your OEM system.

Aftermarket systems provide a higher voltage preout, which enables better sound clarity. If you are gonna use the loc, try tapping the signal after the amplifier, makes it a bit better and stronger, however it is still not gonna sound that great..

I did it and it was EASY!!

here

http://www.toyota-4runner.org/showth...&threadid=9286

Pull the faxtory sub box out, mount the factory amp some how, and add a hi-low converter to the factory sub wires. It will already be low frequency because of the crossover in the JBL amp.

But I thought you had to tear out half the rear end to get to that amp! Wasn't there a detailed thread that someone showed that!? Was I wrong & got this mixed up?

well you have to take thta right rear apart to get to the factory sub and amp, yah. but when you here your aftermarket sub, the JBL system sounds 10x's better!


well worth the time

I'll have to take a closer look now. From an earlier thread it look like the whole rear part of the Runner had to be disassembled just to get to that amp & speaker. From your pix it just looks like that smaller panel just pops out (I thought that panel was molded to the larger piece.).

I had kinda given up on the whole thing because of above, and that a mini woofer wouldn't fit under the front seat well.

It is! but it is joined together like rivets, and I just drilled them out. I have been meening to order the trim piece for a non 10spk to replace it but dont have the money right now.

just dont rush and be patient.

Oh, so once you got the big panel out you were able to drill the rivits off the smaller one - right?

Did you then do an external speaker, or put it in the existing enclosure?

I'd check out if the snap in trim piece works on that surround piece before drilling out the rivets....I talked to my parts guy and he thought that you had to order the entire trim panel to accomodate the snap in removable door.......it was some big bux if I remember correctly.

the large pieces are the same just the 10spk has a panel "melt" riveted to it. the snap in works. My dad has a 4th gen with out jbl and i tested it