8 ohm vs 4 ohm
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What is the difference between an 8 ohm sub and a 4 ohm sub?
I just purchased a new RF Punch 3812 by mistake (8 indicating 8ohms) instead of a 4 ohm 3412. I installed it and it doesn't sound as loud as i think it should. I was trying to run it with a JBL amp at 4 ohm. I am going to try and return it for the proper one tomorrow without using it anymore but was curious what the difference is. Thanks.
I just purchased a new RF Punch 3812 by mistake (8 indicating 8ohms) instead of a 4 ohm 3412. I installed it and it doesn't sound as loud as i think it should. I was trying to run it with a JBL amp at 4 ohm. I am going to try and return it for the proper one tomorrow without using it anymore but was curious what the difference is. Thanks.
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Heres the deal: 8 ohm presents twice as much resistance than 4 ohm, so it will take a little more "gain" from a 4 ohm amp to make an 8 ohm speaker sound good. If you had an 8 ohm amp, it would sound okay.
To clarify a bit further, a 4 ohm amp powering a 4 ohm speaker will use about the same amount of electrical power from your car (alternator/battery) as a 8 ohm amp with 8 ohm speaker at same wattage.
The reason you don't want to use 8 ohm speakers with a 4 ohm amp is that for the volume you want, your chips need to run more power through them, which decreases their life, so it'* not recommended.
To clarify a bit further, a 4 ohm amp powering a 4 ohm speaker will use about the same amount of electrical power from your car (alternator/battery) as a 8 ohm amp with 8 ohm speaker at same wattage.
The reason you don't want to use 8 ohm speakers with a 4 ohm amp is that for the volume you want, your chips need to run more power through them, which decreases their life, so it'* not recommended.
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You never stated which JBL amp you have. If you have one of the class D'* bp150. bp300.1 or bp1200.1 you will need a dual 4 ohm sub
If you have any of the othe BP series amps you will need the 4 ohm sub
If you have any of the othe BP series amps you will need the 4 ohm sub
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Whoa. Where'd TaylorD go? An 8 ohm sub will pull half the current a 4 ohm sub will.
To put it simply, ignore all the marketiing BS, when you bridge a 4 ohm sub, you will THEORETICALLY get twice the power out of your amp as you would with an 8 ohm sub.
When bridging an amp it sees half of the ohms (impedance) of your driver. Basic electical laws. Feel free to abuse me due to the fact I've had a few pops..
To put it simply, ignore all the marketiing BS, when you bridge a 4 ohm sub, you will THEORETICALLY get twice the power out of your amp as you would with an 8 ohm sub.
When bridging an amp it sees half of the ohms (impedance) of your driver. Basic electical laws. Feel free to abuse me due to the fact I've had a few pops..
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Also becareful with impedance...... the LOWER the impedance (i.e. the lower the number) the more 'work' the amplifier has to do...not the other way around. Running a 8 ohm sub with a amplifier that is rated for 4 ohms won't do any damage.