# More voice coils = More power handling?



## Ultimateherts (Nov 13, 2006)

Just wanted to know if more voice coils adds more power handling. I know I used to see this all the time in SPL subwoofers. An example being like quad coil 1ohm subwoofers etc...


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## minbari (Mar 3, 2011)

If you are talking about burping a sub with 20kw, then it might. Quad coils are really designed so you can put max wattage from 4 amplifiers instead of just one.

If you are talking about running power that is within more normal amounts, then no. a dual coil with one coil shorted will accept the same amount of power as both coils driven with half as much power. copper or aluminum, which is what VC wire is made from doesnt melt till 800+° F. you would melt the former or set the cone on fire before you glow it red hot and melt it.


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## 07azhhr (Dec 28, 2011)

Multiple coils is generally more for multiple wiring configurations. Most subs that come in both single and dual vc's will still be rated at the same wattage.


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## jhsellers (Jan 7, 2012)

Ultimateherts said:


> Just wanted to know if more voice coils adds more power handling. I know I used to see this all the time in SPL subwoofers. An example being like quad coil 1ohm subwoofers etc...


Generally, yes. But, the two coils on a dual coil driver might not be as "large" as the one on a single coil driver. Both coils may have to fit within the same physical constraints as the single coil, and thus each of the dual coils might not rated for as much power as the single coil unit. So, you may not get any additional power handling capability - just depends on the individual driver construction. 



minbari said:


> If you are talking about running power that is within more normal amounts, then no. a dual coil with one coil shorted will accept the same amount of power as both coils driven with half as much power. copper or aluminum, which is what VC wire is made from doesnt melt till 800+° F. you would melt the former or set the cone on fire before you glow it red hot and melt it.


minbari, I'm not sure I understand what you meant to Ultimateherts by "dual coil with one coil shorted" - but I thought I'd caution you about this. You should NEVER run a dual coil driver with one coil and SHORT the non-used coil(s). You CAN run with an unused coil OPEN-CIRCUIT. 

If you run a driver with a non-energized coil shorted, the EMF within the speaker motor and the working coil will cause current to circulate in the shorted coil. This can damage the coil, plus cause unwanted distortion in the driver. 

Just a word,
John


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## minbari (Mar 3, 2011)

jhsellers said:


> minbari, I'm not sure I understand what you meant to Ultimateherts by "dual coil with one coil shorted" - but I thought I'd caution you about this. You should NEVER run a dual coil driver with one coil and SHORT the non-used coil(s). You CAN run with an unused coil OPEN-CIRCUIT.
> 
> If you run a driver with a non-energized coil shorted, the EMF within the speaker motor and the working coil will cause current to circulate in the shorted coil. This can damage the coil, plus cause unwanted distortion in the driver.
> 
> ...


you are 100% wrong. do you really believe that a coil that is designed to dissipate 500watts or more of thermal energy is going to be damaged by the miliwatts of energy that can be generated by electro-magnetic inductance? 

if it is shorted together all it is going to do is raise QTS of the driver slightly by adding a small amount electrical braking to the driver.

read this, it is a great discussion on the topic. specifically read the section by Adire audio

http://www.diymobileaudio.com/forum...io-discussion/144501-ib-one-coil-shorted.html


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## inspector3711 (Apr 11, 2013)

I will say that I recently purchased a dual coil sub that was also available in single coil configuration. I made the decision based on resistance.

The amp I selected is rated at 200 watts RMS into 4 ohms. The single coil sub was rated at 300 watts into 4 ohms.

I selected the dual coil because by wiring the two coils together in series, I can lower the resistance to 2 ohms. The amplifier I chose is rated at 400 watts RMS into 2 ohms. 

So, in that manner of speaking, the dual coil woofer doesn't handle more, but it allows me to draw more wattage from the same amplifier.


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## minbari (Mar 3, 2011)

but that is not what this discussion is about.

if you had an amplifier that put out 300 watts into 4ohms and used the DVC 4+4 and only wired one coil, it will still work just as well as it would if you had an amplifier that was 300 watts into 2ohms and used both coils.

what you are talking about is amplifier loading to produce more power. this has no effect on how much power the sub will handle.


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## inspector3711 (Apr 11, 2013)

Thats basically what I stated. I figured the OP might be confused by the difference.


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## left channel (Jul 9, 2008)

Didn't the Kappa Perfect VQ have a set of inserts that allowed you to run either 1 coil open or 1 coil closed?


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## Hoye0017 (Mar 23, 2010)

left channel said:


> Didn't the Kappa Perfect VQ have a set of inserts that allowed you to run either 1 coil open or 1 coil closed?


Nope. That was some sort of pole piece insert that changed the BL, Qes, and thus the Qts of the driver.

They made them in a vq and dvq version which was single and dual coil respectively.


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## 07azhhr (Dec 28, 2011)

Hoye0017 said:


> Nope. That was some sort of pole piece insert that changed the BL, Qes, and thus the Qts of the driver.
> 
> They made them in a vq and dvq version which was single and dual coil respectively.


This is true for the Kappa but shorting the unused coil vs leaving it open changes multiple things as well. It changes the BL, Qts, Qes, Qms, and Le.


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## Bayboy (Dec 29, 2010)

Adire touched on that....


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