Ohm Question
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what you should do is run speaker wire from the amp but don't hook it up to your subs. play a test tone on your head unit with the volume turned up to where you normailly listen to it. measure the ouptu voltage at the ends of the speaker wire. Here is the formula that I use
VOLTAGE SQUARED DIVIDED BY RESISTANCE EQUALS= POWER. Your ouput voltage will vary as you adjust the gain.
So for example if you get it to read around 39 volts with a 2 ohm load, it should put out 760 watts but i would shoot for around 43 to 45 watts.
VOLTAGE SQUARED DIVIDED BY RESISTANCE EQUALS= POWER. Your ouput voltage will vary as you adjust the gain.
So for example if you get it to read around 39 volts with a 2 ohm load, it should put out 760 watts but i would shoot for around 43 to 45 watts.
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if they are dual 4ohm, then you can run 2 speakers at 4ohm.
however, you sig says P312D2 - which is a model number for ohm DVC.. P312D4 would be dual 4
however, you sig says P312D2 - which is a model number for ohm DVC.. P312D4 would be dual 4
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I guess i need to change the sig.
I am not 100% sure what I have. I do know this, a week ago we put a meter to the speaker jack on the box and it read 1.85-1.97. So thats 2 Ohms. The guy that metered them and installed them said they were 4 ohm speakers and there dual voice coil. So I guess he wired the dual voice coils together..making it 2 ohm load. I am not sure how that works.
The other thing I know is that the amps are running in 2 Ohm. That is what confuses me. Everything in my trunk is 2 Ohm load, but the speakers are 4 Ohm speakers..
I don't know. Just confused.
I am not 100% sure what I have. I do know this, a week ago we put a meter to the speaker jack on the box and it read 1.85-1.97. So thats 2 Ohms. The guy that metered them and installed them said they were 4 ohm speakers and there dual voice coil. So I guess he wired the dual voice coils together..making it 2 ohm load. I am not sure how that works.
The other thing I know is that the amps are running in 2 Ohm. That is what confuses me. Everything in my trunk is 2 Ohm load, but the speakers are 4 Ohm speakers..
I don't know. Just confused.
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Brian, I orrigionally thought I had P3D122 - 2 Ohm speakers, but the guy at the shop says there 4 ohm. That is why I am soooooo confused. The jack ports show 2 Ohms on them. But if they are DVC, I guess each VC is 2 OHm..hence the 4 OHM total speaker rating. I guess.
toastedoats,
There is one jack per speaker. The jack has on set of inputs. 1 (+ )and 1 (-)
So this one jack goes to both voice coils in the one speaker. How they are wired up inside I am presuming are like the picture above, posted by Plurr.
I am guessing. But what I stated on the box is what I see. One Jack per speaker.
toastedoats,
There is one jack per speaker. The jack has on set of inputs. 1 (+ )and 1 (-)
So this one jack goes to both voice coils in the one speaker. How they are wired up inside I am presuming are like the picture above, posted by Plurr.
I am guessing. But what I stated on the box is what I see. One Jack per speaker.
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you should be able to combine the negatives on the negative bridge terminal and the positives to the positive and the amp will read a 4 ohm mono load which would give each sub right at 750 watts.
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Take one of your P3'* out of the box and look at the sticker on the magnet for the model number.
If the model number is;
P3D412 = DVC 4 ohms per coil
OR
P3D212 = DVC 2 ohms per coil
Here are the links for the 2 different P3'*
Click on the woofer wiring tabs on the bottom of these links, to see wiring config.
4 ohm DVC
http://www.rockfordfosgate.com/produ...n_US&p_status=
2 ohm DVC
http://www.rockfordfosgate.com/produ...n_US&p_status=
Is this the Amp your looking at buying ?
Click on the Specification tab at the bottom of the linked page.
http://www.rockfordfosgate.com/produ...n_US&p_status=
This amp can handle 1, 2 & 4 Ohm loads
The load on the amplifer is determined by how you wire your subs.
Think of it this way the amplifer has eye'* and can only see what ever resistance you show it by way of wiring your subs.
Less resistance = more power (unless you drop the load too low then you put the amp into protection ex. 0.5 ohm load)
Ex.
750 watts x 1 at 4 ohm
2000 watts x 1 at 1 ohm
Dutch
If the model number is;
P3D412 = DVC 4 ohms per coil
OR
P3D212 = DVC 2 ohms per coil
Here are the links for the 2 different P3'*
Click on the woofer wiring tabs on the bottom of these links, to see wiring config.
4 ohm DVC
http://www.rockfordfosgate.com/produ...n_US&p_status=
2 ohm DVC
http://www.rockfordfosgate.com/produ...n_US&p_status=
Is this the Amp your looking at buying ?
Click on the Specification tab at the bottom of the linked page.
http://www.rockfordfosgate.com/produ...n_US&p_status=
This amp can handle 1, 2 & 4 Ohm loads
The load on the amplifer is determined by how you wire your subs.
Think of it this way the amplifer has eye'* and can only see what ever resistance you show it by way of wiring your subs.
Less resistance = more power (unless you drop the load too low then you put the amp into protection ex. 0.5 ohm load)
Ex.
750 watts x 1 at 4 ohm
2000 watts x 1 at 1 ohm
Dutch
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Thanks guys,
I guess that is what it boils down to is opening the sub box and seeing for myself what is in there and how it is wired up.
I was so hoping to not do that. But I guess I will have to.
Thanks for all your inputs.
I'll get back to you as soon as I do this.
I guess that is what it boils down to is opening the sub box and seeing for myself what is in there and how it is wired up.
I was so hoping to not do that. But I guess I will have to.
Thanks for all your inputs.
I'll get back to you as soon as I do this.