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2 Ohms vs. 4 Ohms...what does all this mean...

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Old 06-19-2005, 10:21 AM
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DerekJL
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Default 2 Ohms vs. 4 Ohms...what does all this mean...

Hello, I just purchased a JBL CS200.1 amp to power an Infinity Kappa Perfect 12.1 sub. The specs are telling me it will do 338 Watts X 1 at 2 Ohms and 230 Watts X 1 at 4 Ohms. When it is hooked up to the sub, which amount of wattage will it be producing? And why is power at 2 Ohms always more? Thanks, I am VERY new at this stuff....
Old 06-19-2005, 10:59 AM
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VPUPPY
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each speaker has a difference impedance(resistance) load. most speakers for car audio are rated at 4 ohms. some speakers are single voice coil and some are dual voice coils. depending on how you wire things you can create a different impedance load. if you hook up two 4 ohm speakers in parallel(the positive terminals are together and the negative terminals together) you will get a 2 ohm load. if you have a single sub that is a dual voice coil, you can wire it to create a 2 ohm load(refer to its instructions). the difference ohm rating on amps means that the amp produces different power at difference impedance loads(depends on how you wire your subs) the amp you bought is a mono bock amp meaning that the terminals that you hook your speakers up to are the same(should be two sets of + and - terminals). so if you hook up a 4 ohm speaker, the amp will output 230 watts. if you hook up a second speaker in parallel, the amp will output 338 watts. this is just the basics of what your asking, everything is dependent on your amp and sub combo. if you did not understand something, post back your questions.
Old 06-19-2005, 11:19 AM
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19.3secS2K
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I hope his post didn't throw you off. if you don't know all the jargon or the theory of electronics, it's easy to get lost.

like he said, ohms are resistance in the wires. If you have more resistance, less power will be drawn. The lower the ohm rating, the more effecient your amp will run. However, if you overwork your amp, it can easily overheat. But that shouldn't be a problem for you.
Old 06-19-2005, 12:46 PM
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cobbcustomz
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I believe that the Kappa Perfect that you have is Dual 4 Ohm VC so if wired in Parallel The speaker would be at a 2ohm load drawing the 338 watts
Old 06-19-2005, 01:26 PM
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I guess the easiest way to understand it is, you want to wire the subs and or sub to where they have the least amount of ohms that your amp will handle. In other words, if you have a mono amp that is stable at 2 ohms, you could bridge two 4 ohm subs to equal 2 ohms which would give you the most power from your amp. And/or, if you only had one sub with two voice coils, you would want to wire it to 2 ohms. If you had two 8 ohm subs, you would not get all the power from your amp and it would not sound as good(loud). You would have to look at the woofer wiring wizard at www.rockfordfosgate.com to understand the wiring of woofers. That's why it's importat to get the right ohm sub or subs that you plan on using for your amp/amps.
Old 06-19-2005, 10:57 PM
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Originally Posted by Tankard
If you had two 8 ohm subs, you would not get all the power from your amp and it would not sound as good(loud).
I think with low impedance comes something else you are sacrificing.
Old 06-20-2005, 12:41 PM
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Originally Posted by WiLL
I think with low impedance comes something else you are sacrificing.

No. It depends on the amp. Some amps can run at lower ohms. Some amps are stable at 1 ohm, some at two ohms, and others at 4 ohms. For example, a long time ago when i had a punch 150, two 8 ohm subs were ideal for that amp. Bridged they ran at 4 ohms, and thats as low as you could go on that amp. If you bridged two 4 ohm subs on it,2 ohms total, the amp would not have handled it. It would have run hot, clipped off, blown fuses, etc.
Old 06-20-2005, 03:26 PM
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Originally Posted by Tankard
No. It depends on the amp. Some amps can run at lower ohms. Some amps are stable at 1 ohm, some at two ohms, and others at 4 ohms. For example, a long time ago when i had a punch 150, two 8 ohm subs were ideal for that amp. Bridged they ran at 4 ohms, and thats as low as you could go on that amp. If you bridged two 4 ohm subs on it,2 ohms total, the amp would not have handled it. It would have run hot, clipped off, blown fuses, etc.

I understand all that.

I am saying if you are running the same speakers, given the same power, but at different OHMs, will one set sound better than the other?
Old 06-20-2005, 04:19 PM
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97teg
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Although it is debateable whether it will actaully have a significant impact in sound the dampening factor, or the amps ability to control the speaker, will be decreased as the impedence is decreased.

http://www.bcae1.com/

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