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2ohm vs 4ohm

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Old 03-24-2004, 12:23 PM
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SwiftStreetLude
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Default 2ohm vs 4ohm

What exactly is the difference between 2ohm and 4ohm? .. And which is better? .. Ive heard 4ohm is better but can someone elaborate on how this is.

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Old 03-24-2004, 01:18 PM
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SumAccordGuy94
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impedance is hard to explain. Neither one or the other is better... it all depends on how you're powering them. Im sure someone can elaborate on this, i just wanted to clarify that there is no real advantage of one over the other.
Old 03-24-2004, 05:31 PM
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cheezthis
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Impedance is measured in ohms, just like resistance...however impedance differs in one major way; it varies upon frequency.

A 2 ohm load will have twice the amount of current as a 4 ohm load.

You can figure out the rest by reading specs on various amps and subs.
Old 03-24-2004, 06:33 PM
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There are amps out there that produce the same power at 2, 3, and 4 ohm impedance. Not to mention the amps that are not stable at a certain load. You can wire your subs to a certain impedance that you want to present to the amp. Different subs have different impedances, so you will wire the sub(s) differently depending on the impedance of the sub(s) and what the amp is rated for. If you want a two ohm load on your amp (say your amp puts maximum power out at 2 ohms) you will wire your sub(s) in such a way to present a 2 ohm load on your amp. Now, depending on the subs, this is sometimes impossible. Thats why you must carefully plan out your system before you buy it, you could buy an 8 ohm sub and an amp that puts out maximum power at 2 ohms, and you would be screwed because the minimum impedance you can send to your amp would be 8 ohms.

This is a basic rundown on impedance- to learn more go to www.bcae1.com and read up on series/parallel basics and series/parallel impedance.
Old 03-26-2004, 01:06 PM
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2ohm or 4 ohm is the measurement of impedance on the coil of a driver at it's static state(the impedance will change significantly when the driver moves) Usually the less resistance presented to the amplifier the less control at a given power, or less impedance the more distortion.


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Old 03-26-2004, 10:35 PM
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neither one is better than the other.

the impedance choice of your speakers will depend on the amp and number of speakers you are going to use. you will want to match up the impedance load of your speakers to the amp, that will you will use the amp effiecently.
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Old 03-27-2004, 01:06 PM
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Surfacing171
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Originally Posted by WiLL
neither one is better than the other.

the impedance choice of your speakers will depend on the amp and number of speakers you are going to use. you will want to match up the impedance load of your speakers to the amp, that will you will use the amp effiecently.
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Old 03-27-2004, 03:03 PM
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illusion
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Originally Posted by WiLL
neither one is better than the other.

the impedance choice of your speakers will depend on the amp and number of speakers you are going to use. you will want to match up the impedance load of your speakers to the amp, that will you will use the amp effiecently.

It does matter if you want to get nitpicky. As I stated above "the less impedance the more distortion", FETs are MORE efficient at higher impedance. You put more stress on an an amp with lower impedance and more stress = more distortion. Generally for subs and for most car audio it doesn't matter, there is enough noise in the environment to make the difference in THD inaudible. Many IASCA SQ competitors choose higher impedance for a truer signal reproduction. There's a reason many home audio systems are still 8 ohm(even though many high end home audio amps can handle as low as a 2 ohm load). The distortion will be more noticeable at lower volumes as the higher the output signal the smaller the percentage of THD is to the signal, in other words the SNR is lower at higher power. Also a PA(Power Amp, FET or whichever you'd like to call it) is MORE efficient at higher impedance, efficiency is a term to describe the amount of wasted energy in a circuit, NOT the amount of power it puts out.
Old 03-30-2004, 09:01 PM
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Originally Posted by illusion
It does matter if you want to get nitpicky. As I stated above "the less impedance the more distortion", FETs are MORE efficient at higher impedance. You put more stress on an an amp with lower impedance and more stress = more distortion. Generally for subs and for most car audio it doesn't matter, there is enough noise in the environment to make the difference in THD inaudible. Many IASCA SQ competitors choose higher impedance for a truer signal reproduction. There's a reason many home audio systems are still 8 ohm(even though many high end home audio amps can handle as low as a 2 ohm load). The distortion will be more noticeable at lower volumes as the higher the output signal the smaller the percentage of THD is to the signal, in other words the SNR is lower at higher power. Also a PA(Power Amp, FET or whichever you'd like to call it) is MORE efficient at higher impedance, efficiency is a term to describe the amount of wasted energy in a circuit, NOT the amount of power it puts out.
youre right about all that....if you wanna get nitpicky.
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