What are dual voice coil subwoofers?


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Dual voice coil subwoofers are a popular choice among car audio enthusiasts who want more flexibility in wiring their sound systems. While typical subwoofers have a single voice coil, dual voice coil (DVC) subwoofers use two separate voice coils, each with its own connections, mounted on one cylinder, connected to a common cone.

Rockford Fosgate subwoofer

Rockford Fosgate's DVC subs can handle lots of power, so you can enjoy bigger bass

The key difference between single and dual voice coil subwoofers is the multiple wiring options DVC subs offer:

  • Parallel: A dual 4-ohm voice coil subwoofer with its coils wired in parallel presents a 2-ohm load to your amplifier. Since an amplifier produces more wattage at a lower impedance, the parallel connection ensures you'll get the most output from your amp. In the same fashion, if you have a stereo amplifier and two DVC subs, wire both subs for 2-ohm impedance (one per channel) for maximum output.
  • Series: Series wiring lets you configure multiple woofers to one amplifier at an acceptable impedance. Wire both coils in series for an 8-ohm impedance, and then wire two 8-ohm subs together in parallel for 4-ohm total impedance (perfect for most 2-channel amps bridged to mono operation). Another example: if you have a high-powered 2-channel amplifier, wire four 8-ohm subs per channel (each channel sees a 2-ohm load).
  • Independent: You can wire each voice coil to a separate channel of your amplifier, if you prefer not to bridge your amp. Independent wiring is a nice option if you're wiring two DVC subs to a 4-channel amplifier — one voice coil per channel. Just make sure the signal going to each coil is exactly the same, or the differences will cause distortion.

DVCs and high-performance amplifiers

Rockford Fosgate T1000-1bdCP amplifier

Look for an amp that's stable at 1 ohm, like this Rockford Fosgate T1000-1bdCP.

Some amplifiers are designed with an unregulated power supply — these amps are favored by mobile audio competitors for their superior performance. An unregulated amp's power increases dramatically when it sees a lower impedance load. For example, an amplifier that produces 75 watts RMS x 2 channels at 4 ohms would double its power to 150 watts x 2 with a 2-ohm load. DVC subwoofers (particularly the dual 2-ohm models) give you the flexibility to wring every bit of power out of this type of amplifier.

Also, if you choose to add an unregulated amp as a power upgrade to your existing DVC subwoofer system, you can simply rewire your subs for optimum impedance. Remember that most car amps are stable down to 2 ohms in normal operation, and to 4 ohms in bridged mode. It's important to check your amp's manual for its operating parameters before hooking up a DVC sub that's wired for low impedance.

A DVC sub offers the same performance whether it's wired in series or parallel. Its power handling levels, frequency response, and other specifications do not change — the only difference is the impedance presented to the amplifier. As a result, you'll need to use the enclosure that's recommended for your sub, no matter how it's wired.

  • Fernando

    Posted on 8/25/2015 1:29:05 PM

    I have a 4 channel amp which is brigded stable at 4ohm only. But my subwoofer has two 4ohm coils. My question is: Can I use one coil only in order to connect my sub to my amp in brigded mode? Or what would you recommend in my case? Thank you

  • Alexander Hrabe from Crutchfield

    Posted on 8/26/2015 9:12:30 AM

    Fernando, you could wire your sub that way, but you'll need to ensure that your not overpowering sub. Alternatively, you can wire your sub like this, using both voice coils. In this scenario, you'll want to make sure you're not underpowering your sub. You want to make sure the amp is capable of supplying from 75% to 150% of the sub's RMS rating.

  • Scott Trout from Perham

    Posted on 9/8/2015 2:15:07 AM

    When I purchased my system 10 years ago, it was professionally installed by a local car audio specialist. He selected all my equipment for me since I knew nothing about the stuff at the time. I now have a little more understanding but am by no means an expert so bear with me. My system contains a 10" kicker cvr with 4ohm DVC (wired in parallel I think. There is a wire bridging one negative and one positive together and the other two terminals connect to the amp of course) powered by a 200 watt clarion APA-250 2 channel amp (bridged). My sub is making a rattle in the surround at certain frequencies so I'm looking to replace it if it can't be cheaply repaired. My question is, am I going to be safe buying a 2ohm SVC sub and will I notice any sound difference? Wouldn't my amp currently be pushing against an 8ohm impedance? Another factor is my system is going from my car trunk to the rear seat of my silverado and I plan on using a smaller sealed box down firing under my seat as opposed to my larger ported box. Thank you for your time and expertise.

  • Anna Kiphuth from Buffalo

    Posted on 9/15/2015 12:30:39 PM

    I have a boss mono amp 2800wt, cl D, 1 to 8ohms, 2 10in subs, 1100rms each, dvc 4ohm in a fitted sealed box, only .1cuft short on air space for speakers... wired in parallel.. had professional installed, had 2nd set of speakers burn up? please help. all wires are doubled up, all neg from amp to speaker and same with pos. all wiring diagrams show 1 leading to the other. ( 4 wires on amp pos/neg 2 leds to box port than doubled again to each coil 4 wires 2 leds each speaker.) amp has great THERMAL/OVERLOAD/SHORT PROTECTION,, But why is this happining, seems like amp is hot and speakers are if course if buring up. about 80°+ outside, hot and it happens when i turn it up and use the power ? this amp was made for low Independence at 1ohms?

  • Alexander Hrabe from Crutchfield

    Posted on 9/16/2015 9:17:39 AM

    Anna, take a look at this article. Depending on how you're wiring your system and for what impedance, it could be that you're actually underpowering your subs. Before you buy another pair of subs, work with your installer to make sure that your amp and the subs you want are a good match. Keep in mind that if you purchase from us, you have the benefit of lifetime tech support to troubleshoot your system.

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