Upgrading subwoofer amp and speaker while retaining the stock radio unit

doktormane

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The subwoofer in my 03 Rubi stopped working and I am going to replace it with the Kicker Comp RT672 Dual Voice 2 Ohm. Is there any way to upgrade the subwoofer amp that is in the console without changing the head unit? I want to keep the stock radio because frankly it looks much better than the aftermarket ones available. I am not an audiophile so I don't want state of the art sound.
 
If you haven't looked thru it yet, this thread might have some answers for you. If I remember correctly, the factory amp is wired with speaker level inputs. You'd want to find an aftermarket amp that has that feature. This is speculation and hopefully someone with more knowledge can correct me if I'm wrong, but with a dual voice coil subwoofer, you may be able to wire a 2-channel amp with one channel for each coil.
 
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If you haven't looked thru it yet, this thread might have some answers for you. If I remember correctly, the factory amp is wired with speaker level inputs. You'd want to find an aftermarket amp that has that feature. This is speculation and hopefully someone with more knowledge can correct me if I'm wrong, but with a dual voice coil subwoofer, you may be able to wire a 2-channel amp with one channel for each coil.
Thanks for the reply. I am also confused by the impedance. Apparently the stock subwoofer is a dual voice 2 ohm which through the way it is wired (series, or parallel, I forgot which one) it is brought down to 1 ohm. What would happen if I were to wire a 4 ohm dual voice subwoofer to the factory amp?

Cheers,
Dan
 
Thanks for the reply. I am also confused by the impedance. Apparently the stock subwoofer is a dual voice 2 ohm which through the way it is wired (series, or parallel, I forgot which one) it is brought down to 1 ohm. What would happen if I were to wire a 4 ohm dual voice subwoofer to the factory amp?

Cheers,
Dan

If everything else is kept stock, you'll want to wire it exactly like stock. I can't recall the model, I think its the same one, but I used the popular replacement Kicker CompRT 6 3/4” ( dual voice coil 2 Ohm/150W RMS) with my aftermarket head unit. I retained the stock wiring and sub woofer amp. I wired it just like stock, using the stock subwoofer amplifier wiring as a guide. Works good for what it is...a nice cheap replacement.
 
Thanks for the reply. I am also confused by the impedance. Apparently the stock subwoofer is a dual voice 2 ohm which through the way it is wired (series, or parallel, I forgot which one) it is brought down to 1 ohm. What would happen if I were to wire a 4 ohm dual voice subwoofer to the factory amp?

Cheers,
Dan

Two 2-ohm loads wired in parallel will result in a 1-ohm load. Wiring a 4-ohm DVC the same way would result in a 2-ohm load. I think that will result in reduced output of the amp and thus lower volume from the sub. I don't know if there are any other negative effects.

You mentioned a 2-ohm DVC in your original post. Are you looking at a different subwoofer now? If you're planning to replace the factory amp with an aftermarket unit anyway, don't worry about how the factory amp connects to the sub. Just make sure the subwoofer you buy is compatible with the amp you buy and the amp has speaker level inputs if you want to wire it to the factory head unit.
 
Get rid of the factory head unit. By keeping it you are seriously limiting what your stereo could be.

Agreed. Some seem to think the stock units are decent, but I just don't care for them. I replaced the head unit in my TJ for the modern amenities and also replaced all speakers and the sub. But, I kept the stock wiring and went with super efficient speakers that don't require much power to drive. No amp, just 22W per channel from the single DIN Kenwood head unit, while using the upgraded Kicker Sub with the stock sub amplifier. I wanted to keep the TJ simple, more old school, so the single DIN is great for me and the sound is good, especially with the Noico sound dampening and hard top.

On my '16 JK, different story completely. I went for a more powerful replacement that would fit its more modern styling. Double DIN, big screen, two amps, rewired new speakers (components front/coax rear), custom sub, backup camera, android auto etc. It is amazing what you can do for the money these days if you install on your own. In a Jeep especially, and with sites like Crutchfield, it's so easy I would have it no other way.
 
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Agreed. Some seem to think the stock units are decent, but I just don't care for them. I replaced the head unit in my TJ for the modern amenities and also replaced all speakers and the sub. But, I kept the stock wiring and went with super efficient speakers that don't require much power to drive. No amp, just 22W per channel from the single DIN Kenwood head unit, while using the upgraded Kicker Sub with the stock sub amplifier. I wanted to keep the TJ simple, more old school, so the single DIN is great for me and the sound is good, especially with the Noico sound dampening and hard top.

On my '16 JK, different story completely. I went for a more powerful replacement that would fit its more modern styling. Double DIN, big screen, two amps, rewired new speakers (components front/coax rear), custom sub, backup camera, android auto etc. It is amazing what you can do for the money these days if you install on your own. In a Jeep especially, and with sites like Crutchfield, it's so easy I would have it no other way.
New plan, get somebody to tear the guts of the stock stereo, put in an aftermarket amplifier in it and only keep the volume button and install an aux jack. That's all that I need.
 
New plan, get somebody to tear the guts of the stock stereo, put in an aftermarket amplifier in it and only keep the volume button and install an aux jack. That's all that I need.

I've heard about options for swapping the stock Chrysler stereos with other similar factory ones that have more options (aux jack, BT etc.). Perhaps someone on here can chime in that knows more about this. I think there is a web site that sells these types of units for folks that want to keep the stock look. This sounds like it could be along the lines of what you are looking for.

P.S.
Not sure this is a worthy source or not, but you get the idea...
 
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Agreed. Some seem to think the stock units are decent, but I just don't care for them. I replaced the head unit in my TJ for the modern amenities and also replaced all speakers and the sub. But, I kept the stock wiring and went with super efficient speakers that don't require much power to drive. No amp, just 22W per channel from the single DIN Kenwood head unit, while using the upgraded Kicker Sub with the stock sub amplifier. I wanted to keep the TJ simple, more old school, so the single DIN is great for me and the sound is good, especially with the Noico sound dampening and hard top.

On my '16 JK, different story completely. I went for a more powerful replacement that would fit its more modern styling. Double DIN, big screen, two amps, rewired new speakers (components front/coax rear), custom sub, backup camera, android auto etc. It is amazing what you can do for the money these days if you install on your own. In a Jeep especially, and with sites like Crutchfield, it's so easy I would have it no other way.

And if you want something that looks factory but is a much better head unit than stock, get the Continental unit that @psrivats bought. Hopefully he'll soon post some photos of it installed.
 
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Search on YouTube and buy a pair of 5 1/4 speaker brackets that go where the front 4x6 are. They will sound much better than the tinny 4x6's. I bought a $90 pair of polk audio speakers that sound really nice and provide at least some base.

In addition, my LJ has a sub in the center console.
I went a little different route to not lose space and not spend much money - but the outcome was good!
I took out the crappy factory sub, cut out the lip that it sat in, and installed a Pioneer TS-SW2002D2 subwoofer. It fit nicely, and only costs $70. Helps the sound out a lot, and fits in the center console of my LJ.

Its a dual coil sub just like the factory, and 2 ohm, which is also the same. The red and brown wires are positive, the grey and black are negative (you have to cut the female connectors off as the Pioneer has a spring clip that accepts bare wire.
 
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Just did what you are talking about. Kicker sub and amp and the Polk 4×6 front 5 1/4 on the bar. The stock amp can not push the front 4 speakers. Put in a JVC head and a 4 way amp pushing a true 45w per channel. The sound was absolutely fantastic for 5 minutes. Then the front amp blew. And the speaker outs on the JVC. Replaced the JVC with new JVC but decided to skip the front amp and let the head power the front 4 speakers. 22w per channel from the head should do fine. Wen I got everything re-wired the sound is good. I mean it would probably sound very good to me if I hadn't heard it with the front 4 having an amp first. And I just don't wanna go back under the dash to wire up another amp. The sub sounds great. The fronts just really need more CLEAN power to achieve what they are capable of. So I would highly recommend adding a front 4 channel amp that puts out a true 45w pr so (100w rated per channel gives this). I used a "SCOSHE" brand amp from Amazon. Think I'd go for a better name if (when) I put a new 4 channel amp in.
 
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