Running 5-channel 660 watt amp at 2 and 4 ohms with 1,000 watt RMS 3 ohm sub???

[john.mulvehill 10+ year member]

Hello,

I am purchasing a HO112R-W7 which is a JL 12" W7 sub in a ported box.

Sub details/specs here: JL Audio HO112R-W7 Subwoofer system

As you can see, the sub is 1,000 watts RMS and 2,000 watts peak @ 3 ohms.

However, I want to use my old amplifier which is a JBL 660 watt 5 channel amplifier.

Amp details/specs here

As you can see, the amplifier has different channels running at 2 ohms and 4 ohms (but not 3 ohms like the sub has)

One other thing for reference is the recommended RMS for this particular sub:

Recommended RMS spectrum

My questions are:

1. What will be the RMS going from the amp to the sub based on the ohm difference (2 & 4 ohms on amp, 3 ohms on sub) and factoring in the fact that there are 5 channels on the amp?

2. Based on the color spectrum provided in the one link above about the recommended RMS for this particular sub, can this JBL amp be used with this sub?

Any or comments or tips are appreciated. I know I should ideally be running a 1,000/1 amp to the sub @ 3 ohms but I would prefer to not have to buy another amp at this time. Also, this sub is supposed to be incredibly loud, so I am guessing that the 660 watts RMS (if that what it will truly be putting out despite the ohm difference) might be a little less heavy on my ears //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Thanks!

John

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[gunz4me2 10+ year member]

Ouch, that amplifier outputs 360 watts @ 2 ohms and 225 @ 4 on the subwoofer channel. I'd be willing to bet you could split the difference and assume that you would get roughly 293 watts RMS @ 3 ohms, which will NOT be enough power for your 12w7. Granted, my only experience with the w7 line is my cousin's 13w7 and it was a power hungry sub, even in a ported enclosure.

Worst case, try the amplifier you have now and see if it is enough power for you. If it isn't, just be warned that a quality amplifier that outputs 1000 watts RMS @ 3 ohms generally won't be cheap.