# 5 Channel Amp: 4 ohm F/R with a 2 ohm Sub



## bocajoe (Jan 14, 2015)

My front and rear speakers are 4 Ohms and I have a 10" Sub that is 2 Ohms.

Assuming I have a 5-channel car amplifier with these specs:

75 watts RMS x 4 + 350 watts RMS x 1 at 4 ohms
100 watts RMS x 4 + 600 watts RMS x 1 at 2 ohms
200 watts RMS x 2 bridged at 4 ohms + 600 watts RMS x 1 at 2 ohms

Will the F/R speakers receive 75w x 4 @ 4 ohms and the sub 600w x 1 @ 2 ohms or does the wattage change when mixing 4 and 2 ohms?


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## Holmz (Jul 12, 2017)

No, i think you should be fine.


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## Pr_007 (Jul 14, 2010)

bocajoe said:


> Will the F/R speakers receive 75w x 4 @ 4 ohms and the sub 600w x 1 @ 2 ohms or does the wattage change when mixing 4 and 2 ohms?



Check the manufacture spec sheet, I have seen a few manufactures list out different RMS outputs when mixed..Not all, but a few does change, so check again with the spec sheet


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## Bayboy (Dec 29, 2010)

Only a test will show true power when all channels are loaded down, but how much of a difference will that make audibly? I bet very little to none

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## ominous (Apr 21, 2017)

bocajoe said:


> My front and rear speakers are 4 Ohms and I have a 10" Sub that is 2 Ohms.
> 
> Assuming I have a 5-channel car amplifier with these specs:
> 
> ...


The JL amps are pretty close to those numbers. There are both HD900/5 and RD900/5 amps for sale on this forum.


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## dallasneon (Nov 3, 2005)

You'll get the 4 ohm rated power on the F/R and the 2 ohm rated power on your sub channel. 

You'll get this:
75 watts RMS x 4 at 4 ohms
600 watts RMS x 1 at 2 ohms


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## Alrojoca (Oct 5, 2012)

Yes a 5 ch amp, using their channels individually equals to 3 separate amps 2, 2 ch stereo and 1 mono.

Having a 2 ohm sub to the sub ch will not affect the other channels.


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## Swaglife81 (Oct 15, 2016)

Thats a strong sub channel on a 5 channel amp. What amp is it? I've been looking at 5 channel amps but all the decent prices ones have weak sub channels


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## ominous (Apr 21, 2017)

Swaglife81 said:


> Thats a strong sub channel on a 5 channel amp. What amp is it? I've been looking at 5 channel amps but all the decent prices ones have weak sub channels


RD900/5 is the cheapest 5 channel with a decent sub channel (500x1 at 2 ohms) and it retails at $550. They go up from there.


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## 555nova (Apr 12, 2014)

You can find refurbished keyword excelon xr900-5 for pretty cheap that do the same wattage


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## 20to20 (Mar 3, 2017)

Jl audio xd 1000/5.. [email protected] [email protected]


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