Running a 3ohm sub on a 2 or 4 ohm amp??! Please help me.

[Arkel23 10+ year member]

Is it safe to run a 3ohm Subwoofer(Jl 12W7) on a 1 2 or 4 ohm amp? This is the amp Hifonics BXI 1210D Thank you for your answers in advance and please help me.

Click to read more...

 

[misfit138 5,000+ posts]

Yes, it's safe. The amplifier will see a 3 ohm load and perform accordingly. However, I wouldn't expect that Hifonics amp to provide enough power to utilize the w7 to it's potential. You may be better off with an amplifier that provides a little more power...

 

[kr15 5,000+ posts]

ya, off that amp it might only get about 400rms

 

[Arkel23 10+ year member]

Ok, I thought hifonics was a good amp, what would be a better amp? I also figured it didn't really matter as long as it was pumping out the watts the sub needed.

 

[kr15 5,000+ posts]

Its not that the Hifonics is a bad amp, its just not optimal if you have a 3ohm load. That amp is designed to deliver its power at 1ohm. Now, if you had a BXI2010d for example, it would push the sub alot harder

 

[Arkel23 10+ year member]

Oh, ok I see what you are saying, I thought it was saying 900 watts RMS at 2 ohms, but I forgot it didn't say rms and to divide that by 2. Thank you both!

 

[kr15 5,000+ posts]

well, it is "900 rms at 2ohm" if thats what it says. Brutus are rated at rms, not max. Its just that 1. they are overrated, and 2. 3ohm power will be less than 2ohm power

 

[Arkel23 10+ year member]

Oh ok, I gotcha and I went back and looked and it does say that its 900 rms at 2 ohms, and do you know how to hook a sub up to a computer, just while I'm getting my car cleaned?

 

[PioneerSPL1990 10+ year member]

 

[n2audio 5,000+ posts]

Very true Pio'90.

I'll take one last shot at it.

misfit -- The 12w7 needs 750-1000w rms to come to life. Obviously, it's 3 ohms.

The bxi1210d is rated for 1200w at 1 ohm, 900w at 2 ohms and 450w at 4.

Since you'd be running it at 3 it will produce somewhere between 450 and 900w. Theoretically right in the middle so 675. However, HF's brutus amps have for years been understood to be a little over rated so you should only expect 500-600w out of it.

It would work ok, but since you're paying for a 1200w amp and only getting half that we're trying to tell you there might be a better option out there.

 

[Arkel23 10+ year member]

Pioneer, that was just unnecessary. Well, for NOW I'm going to just get one of those two amps, and upgrade in a month or 2. Thanks for your help.

 

[Arkel23 10+ year member]

And what I should be getting is that, if it were 800 watts at 4ohms, and 1,000 at 2ohms, I would be getting somewhere like 850-900 correct?