Can JL Audio MX650 speakers be driven at 2 Ohms?

[GTBRMC]

I see from http://www.jlaudio.com/mx650-ccx-cg-wh-marine-audio-mx-series-speaker-systems-91761 that JL Audio MX650 speakers are "system nominal impedance 4 ohms"...

But can they be driven at 2 Ohms? If so, what compromises / risks does that create?

 

[OrangeTJ]

You don't drive a speaker at lower ohms. That's a measure of the electrical resistance of the speaker and the resultant load they place on an amplifier. The real question is can you run your amplifier into the load presented by the speakers. If you were to put two 4 ohm speakers in parallel, that would present a 2 ohm load to your amplifier. Most aftermarket amplifiers can drive a 2 ohm load (not when bridged, though). In any case, the impedance of a speaker is what it is.

 

[lashburn1]

^^^ what he said.
Speakers are dumb

 

[GTBRMC]

Ah, good point. Been a long time since my circuits class.

I am considering using a JL Audio M400/4 to drive a pair of MX650s on the swimdeck.
If I go that route, I will probably reserve a pair of channels for a sub to be added later.
Really, just trying to re-learn all of this.
http://www.jlaudio.com/m400-4-marine-audio-m-series-amplifiers-98271

Thanks for pointing out my ignorance so concisely.

 

[OrangeTJ]

With that amp, for the time being you could bridge it down to 2 channels and run one MX650 off of each. That way, each of the 4 channels would effectively see a 2 ohm load, resulting in a lot of power to the MX650s. Maybe too much. I'm looking at that amp as a possibility to run 4 MX650s or MX770s (haven't decided yet) inside my boat.

 

[brockhals]

If you're planning to run a sub anyway (at some point), I'd do a 500/3 instead. Still gives you 100 watts for each 650, plus 300 watts for a sub

 

[GTBRMC]

Plan is slowly coming together...

 

[txav8r]

Your going to love those speakers. I am not certain your reserving enough with a 400/4 for the sub. I have a 600/6 and a 500/3 to drive 8 JL MX650's and the 10" JL sub. That gives a nominal 100w to each speaker and 300 to the sub at 14.4v It is stated to be less at 12.2V but as @David Analog always says, JL Amps deliver their rated 14.4 power at 12.2. But I could also swear that Odin told me that even though it is 400, it is more like 240W total, or 4 amps internally rated 60w each. David?

 

[GTBRMC]

I think I may take @brockhals advice and go with the M500/3.

@txav8r , you were 100% correct about build quality! Very, very solid in the hand.
I can't wait to get them installed and hear 'em.

 

[David Analog]

Your going to love those speakers. I am not certain your reserving enough with a 400/4 for the sub. I have a 600/6 and a 500/3 to drive 8 JL MX650's and the 10" JL sub. That gives a nominal 100w to each speaker and 300 to the sub at 14.4v It is stated to be less at 12.2V but as @David Analog always says, JL Amps deliver their rated 14.4 power at 12.2. But I could also swear that Odin told me that even though it is 400, it is more like 240W total, or 4 amps internally rated 60w each. David?

PasMag tested and reviewed the JL Audio XD500/3 amplifier. The review revealed that the amplifier delivered about 135% of its rated power, maintained its 14.4 volt rated power even with a 12.6 volt supply, and maintained 97% of its 1 kHz rated power across the entire audio bandwidth.
The JL Audio XD400/4 is similar in its abilities compared to its conservative ratings. Bridged, the 400/4 will deliver 2 X 280 watts with a 14.4V supply and 2 X 200 watts with a 12.6V supply, which is a bit rich for an MX series coaxial.
Most would select one amplifier versus the other, between the 500/3 and 400/4, based on the impedance of their single subwoofer selection. But even with a 4-ohm sub, I'd have to give the edge to the headroom gained with an amplifier having the largest power supply which is likely to be the 500/3.

 

[GTBRMC]

PasMag tested and reviewed the JL Audio XD500/3 amplifier. The review revealed that the amplifier delivered about 135% of its rated power, maintained its 14.4 volt rated power even with a 12.6 volt supply, and maintained 97% of its 1 kHz rated power across the entire audio bandwidth.
The JL Audio XD400/4 is similar in its abilities compared to its conservative ratings. Bridged, the 400/4 will deliver 2 X 280 watts with a 14.4V supply and 2 X 200 watts with a 12.6V supply, which is a bit rich for an MX series coaxial.
Most would select one amplifier versus the other, between the 500/3 and 400/4, based on the impedance of their single subwoofer selection. But even with a 4-ohm sub, I'd have to give the edge to the headroom gained with an amplifier having the largest power supply which is likely to be the 500/3.

Thanks for your input, David. Always appreciated. I am assuming the M and XD are essentially similar other than more moisture hardening and a corresponding higher price point on the M, is that correct?

I am thinking I will go with an M300/5 amp and the MX10IB3 or the M10IB5 sub...depends a bit on the money situation and spousal tolerance, of course.

Anyone have any thoughts on the M vs MX sub?

If all goes to plan, I will likely approach Odin on a package with the sub, amp, mounting ring, etc. plus a WS-420 in a couple of months. Dialing in on the target!

 

[txav8r]

I think you meant the 700/5 didn't you? The sub you want is the M10iB5.

 

[txav8r]

Or you could do the 600/6 and use two channels together on the sub I think.

 

[GTBRMC]

No, meant the M300/5, to drive the two swimdeck MX650s and the sub. I have a Clarion driving the cockpits coaxes.

What is benefit of M sub over MX?

Edit: I may upgrade the cockpit db651 coaxes and amp to JL, but that would be down the road. Also trying to slide in Seadek this year!

 

[txav8r]

Sorry, I got lost in the number of speakers. I thought we were talking 4 in the boat. Does JL make a 300/3 in the marine version? The JL Amps are all the same internally pretty much. The XD is not marine rated and the M is. It is external stainless hardware and corrosion coatings that the M has.
I will Look at the subs again, but the only two 10" JL's recommended generally is the air suspension and the IB. And both are M10's.

 

[txav8r]

The mx series sub is only rated 50-175w. The M series is 75-250w. In an open air boat, the mx is going to be less than you want. It is good for placement in a cabin really, not open air.

 

[txav8r]

But you can drive the M10W5 enclosed or the M10iB5 infinite baffle with 180-200w very well.

 

[GTBRMC]

The mx series sub is only rated 50-175w. The M series is 75-250w. In an open air boat, the mx is going to be less than you want. It is good for placement in a cabin really, not open air.

Ah, got it. I was missing that. Makes sense. Funny how, at least in boating, the better solution almost always costs more $$$!

 

[txav8r]

Yeah, but the best bang for the buck on a 6.5" JL is the MX, not the M! So sometimes the better solution doesn't cost more!