2005 TJ Audio Upgrade Help: 1 ohm vs 2 ohm Question

rxthurm

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Hello. New here. Just recently purchased a 2005 X w Impact Orange only 33k miles. Super happy with it. I’ve been lurking on here regarding upgrading the audio system and need some help...

My plan is to update stereo to Sony MEXGS820BT. I’m going to replacing dash and roll bar speakers with Polk DB522 (with adjustment plates. I’m going to start with boom mat + poly fill enclosures for those speakers. I will be powering the speakers from the stereo.

I’m having trouble with the sub/amp combo. I’m opting or forgo just doing the powered subwoofer in the console and do a legit separate amp and subwoofer set up. I’m planning on either either replacing with Kicker CompRT 6.75” in original housing (with mods) or I’ve seen a video using a Pioneer slim box and fitting the 8” CompRT in the console with slight modifications. In the video with 8” sub, he used the 1 ohm/voice coil and the Kicker CX300.1 (which has now been replaced by CX400.1).

I’ve seen a lot of people use the PX series from kicker (either 200.1 or 200.2).

My question is how/why do you know to use the 1 or 2 ohm/voice coil sub and how do you know which Kicker amp (PX200.1, PX200.2, CX 400.1) to match it with? FWIW, I emailed Kicker directly and they suggested PX200.1 amp with CompRT 1 ohm/voice coil speaker wired in parallel fashion. Crutchfield responded with CompRT 2 ohm/voice coil and CX400.1 amp.

Can some help me with this?!?!?! Thanks.
 
Seems like you would want a 2 ohm/voice coil wired in series, not parallel. Parallel 1 ohm coils would result in a 1/2 ohm final impedance, which would fry most amplifiers.

That amp is rated at 150 watts RMS at 4 ohms, which is the same power rating as the CX400.1. The goal is to match the RMS and peak power ratings, and not go below the minimum impedance of the amplifier.

That amplifier is 1 ohm stable, so you could run 2 ohm in parallel without damaging the amplifier. But running 1 ohm in parallel is usually not done because most consumer amplifiers of that size are not 1/2 ohm stable. The issue with running it at 2 ohms wired in parallel (1 ohm net impedance) is that the 400 watt rating of the amplifier could easily toast the sub and burn up the coils. It won't damage the amp unless the subwoofer shorts out, which can happen.
 
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There are often two pairs of 1 ohm voice coils and terminals on subwoofers which are usually wired in series with each other to give you a 2 ohm impedance. I don't believe that amps with 1 ohm outputs are common. The OE subwoofer my TJ came with was like that.
 
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Seems like you would want a 2 ohm/voice coil wired in series, not parallel. Parallel 1 ohm coils would result in a 1/2 ohm final impedance, which would fry most amplifiers.

That amp is rated at 150 watts RMS at 4 ohms, which is the same power rating as the CX400.1. The goal is to match the RMS and peak power ratings, and not go below the minimum impedance of the amplifier.

That amplifier is 1 ohm stable, so you could run 2 ohm in parallel without damaging the amplifier. But running 1 ohm in parallel is usually not done because most consumer amplifiers of that size are not 1/2 ohm stable. The issue with running it at 2 ohms wired in parallel (1 ohm net impedance) is that the 400 watt rating of the amplifier could easily toast the sub and burn up the coils. It won't damage the amp unless the subwoofer shorts out, which can happen.
So I spoke with Crutchfield again and they recommended using the PX200.1 and the 1Ohm CompRT....this seems to be counter to what you’re saying??
 
The 1 ohm comp RT could be wired to be 2 ohm in series. Is the PX200.1 2 ohm stable?

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How many watts are you trying to send to the kicker ideally?

Kicker can often handle more than advertised. I've had an old CVR 10" in my truck for years running on 400 watts RMS that is only rated for something like 300w.
 
Wow. That amplifier is 1/2 ohm stable. In that case get a dual 1 ohm and wire it in parallel
***UPDATE***
After consults from here, Crutchfield, and Kicker CS, this is what I’ve found.

If you want to go the route of using the Kicker CompRT 6.75” and original housing, it’s suggested to use the 1 Ohm version, the PXA200. amp, wire it in parallel, and utilize a 10 gauge amp wiring kit.

If you want to use an 8” Kicker CompRT with the Pioneer 8” slim box placed in the console, it’s suggested to use the 1 Ohm version, the CXA400.1 amp, wire it in a series with an 8 gauge amp wiring kit.

It also seems that there are more than one way to skin a cat and people may do it differently.

Here is the link to the 8” sub upgrade I’m trying to duplicate. If 6.75” is great, 8” must be better, right?!


RT
 
***UPDATE***
After consults from here, Crutchfield, and Kicker CS, this is what I’ve found.

If you want to go the route of using the Kicker CompRT 6.75” and original housing, it’s suggested to use the 1 Ohm version, the PXA200. amp, wire it in parallel, and utilize a 10 gauge amp wiring kit.

If you want to use an 8” Kicker CompRT with the Pioneer 8” slim box placed in the console, it’s suggested to use the 1 Ohm version, the CXA400.1 amp, wire it in a series with an 8 gauge amp wiring kit.

It also seems that there are more than one way to skin a cat and people may do it differently.

Here is the link to the 8” sub upgrade I’m trying to duplicate. If 6.75” is great, 8” must be better, right?!


RT

Which way did you end up going? Been wondering if you could fit an 8 in the stock box with just a bit more dremeling.