# Is it possible to wire two 4-ohm DVC subs into a 2 ohm load?



## twofournineseve

I've heard both yes and no.


Wouldn't it work if I just used one voice coil to wire it instead of two?


I have a monoblock amp. (Hifonics ZRX1500.1D)


My subs are Rockford Fosgate P3's (12")


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## tundrSQ

no but you can get to 4 ohm.....not great...a little low on power at 4 ohm....or go to 1 ohm, just make sure you have plenty of ventilation.


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## RCbridge

What are you trying to do?

2 of those 4ohm subs wired in parallel will present a 2 ohm load to that amp, or in series will present an 8ohm load to the amp.

That amp specifies it's power output for a given load so if you present a 2ohm load it states 1kw.


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## tundrSQ




> Quote:
> Originally Posted by *RCbridge*  /t/1467250/is-it-possible-to-wire-two-4-ohm-dvc-subs-into-a-2-ohm-load#post_23191698
> 
> 
> What are you trying to do?
> 
> 2 of those 4ohm subs wired in parallel will present a 2 ohm load to that amp, or in series will present an 8ohm load to the amp.
> 
> That amp specifies it's power output for a given load so if you present a 2ohm load it states 1kw.



They are 4 ohm dual voice coil subs, so wiring each VC in parallel and then each sub in parallel will present a 1 ohm load.


wiring each VC in parallel and then each sub in series will be a 4 ohm load.


and then series and series again will be 16 ohm.


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## Warren_G

You only need to use one coil on each sub, then run them in parallel and you will have a 2 ohm load. The second voice coil has two purposes; to allow flexibility in the impedance that you present to the amp, and to be able bridge a non-bridgeable amp to sum a stereo signal into mono. Using only a single coil will not affect any spec of the sub other than how much power you could put to it if the coils were in series. In parallel, they have the same power handling. Efficiency may also be affected, so you might want to do some testing of using both coils and running the subs in series, but I would wager that you will hear an improvement by using only one coil and creating a 2 ohm load.


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## cubdenno




> Quote:
> Originally Posted by *Warren_G*  /t/1467250/is-it-possible-to-wire-two-4-ohm-dvc-subs-into-a-2-ohm-load#post_23217974
> 
> 
> You only need to use one coil on each sub, then run them in parallel and you will have a 2 ohm load. The second voice coil has two purposes; to allow flexibility in the impedance that you present to the amp, and to be able bridge a non-bridgeable amp to sum a stereo signal into mono. Using only a single coil will not affect any spec of the sub other than how much power you could put to it if the coils were in series. In parallel, they have the same power handling. Efficiency may also be affected, so you might want to do some testing of using both coils and running the subs in series, but I would wager that you will hear an improvement by using only one coil and creating a 2 ohm load.



What about the T/S parameters being affected? Which in turn will cause the enclosure requirements to change. Actual thermal power handling should be very close to the same as there is the same amount of copper/aluminum that will heat up.


I suggest that if you are going to only power a single coil of a dual coil woofer you short the non used coil. This helps keep the unused coil from "influencing" the performance of the woofer.


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## Warren_G

The Thiel Small parameters are mostly influenced by physical characteristics of the sub, so should not be affected much by only using one coil. As well, shorting the terminals of the unused coil WILL have a mechanical impact on the sub, as the electrical energy created by cone movement would be damped, and that would affect T/S and reduce efficiency. Leaving them open would be electrically the same as not having the second set coil present on the sub at all.


I can recall a long time back where some company that made closed-loop servo subs had a demo box that allowed switching between 3 settings, an open sub, shorted coils, and active servo damping, and it was used to show the control exerted on the cone by the damping circuit, and the demo was to simply press on the sub cone and move it by hand. The setting that shorted the coils showed that it would offer more mechanical resistance to movement due to the smaller amount of damping offered by the subs own electrical feedback. A sub moves from the electrical energy put across the coils, and in the same way that a motor and a generator appear to be generally the same, if you manually move a speaker cone electrical eneryg is created and would be measurable across the terminals.

Anyone with a spare sub laying around can try this themselves. Move the cone in and out by hand, then short the terminals and try it again, it will feel that the suspension is stiffer.


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## cubdenno

T/S are the ELECTRO mechanical parameters. While the mass, Xmax, CMS, SD and other physical attributes won't change, the very very important electrical ones will.



Depending on how the T/S specs were taken (series wired or parallel, have never seen a per coil spec given except maybe adire) it will affect the Qe and Qt. Most everything I have ever read has suggested connecting the unused coils positive and negative together as there will be inducted current that can cause unexpected results. Heck some woofer manny's even recommended just running a single coil while attaching a resistor or pot across the unused coils for variable Q/ some rudimentary signal shaping.


Again, I am agreeing that it can be done. Just the box requirements may change as well as power handling will be slightly reduced but should not be much.


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## tundrSQ

This is why i try never to suggest running only one VC in a DVC sub. Sure it can physically be done, and it wont damage the driver. But getting people to agree on what goes on when you do it is always a complicated mess.


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## tolgatnt

Not possible with a monoblock amp, but with a 2-channel amp it is possible.

Here is a pic to show you how to wire them:


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## Dawgzfan37

Technically this image is mislabeled. That is a ONE CHANNEL mono amp that has 2 sets of output leads, both go to the same output channel. Say it's a 4000 watt rms amp, with the subs wired like this each sub would be receiving 2000 watts rms @ 2OHMS. This is no different than wiring both subs together in parallel and running them to just one of the output leads. Both subs would still receive 2000 watts of rms power. Some amps like JL Audio & Rockford Fosgate like to just use one set of output leads (one positive & one negative). But mono amps with 4 leads like this (pos/neg & pos/neg) are still only one channel amps. Hence the outputs could NOT be bridged. It all just depends on the installers preference, and wiring the 2 subs together in parallel to one out put saves some wire (only a foot or two per job, but in a shop that adds up). Really wish they would not title this a 2 channel amp when it's not.
*Technically it could be a 2 channel amp but that would be a poor amp selection & counter-productive when powering 2 identical subwoofers. That's what mono block amps were made for.


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## William McKinney

Dawgzfan37 said:


> Technically this image is mislabeled. That is a ONE CHANNEL mono amp that has 2 sets of output leads, both go to the same output channel. Say it's a 4000 watt rms amp, with the subs wired like this each sub would be receiving 2000 watts rms @ 2OHMS. This is no different than wiring both subs together in parallel and running them to just one of the output leads. Both subs would still receive 2000 watts of rms power. Some amps like JL Audio & Rockford Fosgate like to just use one set of output leads (one positive & one negative). But mono amps with 4 leads like this (pos/neg & pos/neg) are still only one channel amps. Hence the outputs could NOT be bridged. It all just depends on the installers preference, and wiring the 2 subs together in parallel to one out put saves some wire (only a foot or two per job, but in a shop that adds up). Really wish they would not title this a 2 channel amp when it's not.
> *Technically it could be a 2 channel amp but that would be a poor amp selection & counter-productive when powering 2 identical subwoofers. That's what mono block amps were made for.


What if it is a true two channel amp or stereo amplifier


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## William McKinney

Dawgzfan37 said:


> Technically this image is mislabeled. That is a ONE CHANNEL mono amp that has 2 sets of output leads, both go to the same output channel. Say it's a 4000 watt rms amp, with the subs wired like this each sub would be receiving 2000 watts rms @ 2OHMS. This is no different than wiring both subs together in parallel and running them to just one of the output leads. Both subs would still receive 2000 watts of rms power. Some amps like JL Audio & Rockford Fosgate like to just use one set of output leads (one positive & one negative). But mono amps with 4 leads like this (pos/neg & pos/neg) are still only one channel amps. Hence the outputs could NOT be bridged. It all just depends on the installers preference, and wiring the 2 subs together in parallel to one out put saves some wire (only a foot or two per job, but in a shop that adds up). Really wish they would not title this a 2 channel amp when it's not.
> *Technically it could be a 2 channel amp but that would be a poor amp selection & counter-productive when powering 2 identical subwoofers. That's what mono block amps were made for.
> [/QUOT what if it is a two-channel amplifier? Or stereo amp


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## Sonotaguy

Dawgzfan37 said:


> Technically this image is mislabeled. That is a ONE CHANNEL mono amp that has 2 sets of output leads, both go to the same output channel. Say it's a 4000 watt rms amp, with the subs wired like this each sub would be receiving 2000 watts rms @ 2OHMS. This is no different than wiring both subs together in parallel and running them to just one of the output leads. Both subs would still receive 2000 watts of rms power. Some amps like JL Audio & Rockford Fosgate like to just use one set of output leads (one positive & one negative). But mono amps with 4 leads like this (pos/neg & pos/neg) are still only one channel amps. Hence the outputs could NOT be bridged. It all just depends on the installers preference, and wiring the 2 subs together in parallel to one out put saves some wire (only a foot or two per job, but in a shop that adds up). Really wish they would not title this a 2 channel amp when it's not.
> *Technically it could be a 2 channel amp but that would be a poor amp selection & counter-productive when powering 2 identical subwoofers. That's what mono block amps were made for.


You seem very knowledgeable. Can I please ask a question. I bought 2 JL W6 4ohm 2voice coil. My amp is a JL 1200/1 and is stable 1200watt rms for 1,2,4ohm. Should I just wire them at 4ohms 1200watts rms? Would there be any Benefit to wiring down in ohms if the rms is still the same? What’s the absolute best way to hook these things up for lots of sound. Custom built sealed box with 1cf for each sub. Thank you


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## ant101877

Sonotaguy said:


> You seem very knowledgeable. Can I please ask a question. I bought 2 JL W6 4ohm 2voice coil. My amp is a JL 1200/1 and is stable 1200watt rms for 1,2,4ohm. Should I just wire them at 4ohms 1200watts rms? Would there be any Benefit to wiring down in ohms if the rms is still the same? What’s the absolute best way to hook these things up for lots of sound. Custom built sealed box with 1cf for each sub. Thank you


Im not the one you asked but your amp should not have the same watts rms output at 1,2,4 ohms. Any amp will push the hardest at a lower ohm and the least at higher ohms. If its 1200 watts rms at 1 ohm then at 4 ohms will be around 600 watts. But that is just a guess not knowing the exact specs. 
I suggest you double check the specs. And if its 1ohm stable. Wire everything parallel thst should give you a 1 ohm load and the most power.


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