Running One VC on a DVC Sub

First off to say I'm no installer but I do have a sufficient amount of knowledge in car audio.

Though running power to a sub on a single coil (of a DVC driver) is not recommended, it can be done. Whether it's damaging or not, well it is and it isn't. If you are not clipping the amp, and it is sending a clean signal and not sending the driver more power than its mechanical and physical limits it will be fine, though i really don't recommend it. However, running one coil is using only half the sub's capabilities, thus hooking up the second coil will lead to being twice the power. Twice the power theoretically is a 3 dB increase. Also, please see the personal expereince portion of this post as it has extended information.

If you were to wire a sub using both voice coils, you can do so in parallel so your impedence will be 2 ohms or in series, with an impedence of 8 ohms.

Here is some personal experience with this issue:

I was running my dual 2 ohm driver in my vehicle, wired in parallel (1 ohm load) and had no problems at all.  I decided to sell the driver and before I did, I had to hook it up in series (4 ohms) and the driver would not play. Tested the coils and one read 2 ohms, the other read 0. NOT A BLOWN COIL, but a DEAD coil. It wasn't burned because the sub played fine, it moved freely, didn't make any scratching sounds, no distortion, and played just fine off 1 coil. Did I have problems with it? Yes and no. It did work fine, however, it also changed the t/s parameters of the driver with only 1 coil working. This change actually changed alot.  Because of it, I sent the driver too much power.  But since only 1 coil was working, the driver received too much power, thus causing a linear offset and denting the cone slightly and it was only half the cone. Had the coil been working and if i pushed it beyond its limits, there would have been a nice circle from the back plate tapping, but as mentioned it was only a half circle.

Simply said, you can run a DVC driver off one coil, but it is not recommended since it changes the thiel/small parameters and can cause damage to the driver once physical and/or mechanical limits are exceeded.

JL Audio's website has a great section explaining the problems with wiring one voice coil.  It can be found under their "tutorials" section and then you click on "Dual Voice Coils".  It basically says that technically it can be done, but you better know why you are doing it and the effects it will have on power and SQ.  Check it out!

I was reading the forum topic "running one 4 ohm vc on a dvc sub" wich is now closed, so I could not post any questions. So i'll ask them here and maybe someone can answer them for me. One of the replies mentioned running a varible resistor to adjust Q's on the second coil of a DVC sub.

   ""I have actually used the second voice coil for a system "tuning" device. By adding a fixed or adjustable resistor, you can actually adjust the elctrical Q of the woofer, ( ala this article, posted by Steven Kephart of Adire Audio) which will affect the toal Q of the system. Nice. Thanks, Steven! ""

When I tried the link it's dead, does not exist any more, gone.

Does anybody know how to do this. I sounds interesting and I'd like to try it. I'm running a JL 6w10 on a Infinity REF 611 in 96 Mustang. Sometimes it's abit much.

You mean its too loud?  Turn the gain down a notch.

The w6 is a real flat woofer to begin with. . .

"Q" refers to the overall slope of the bandpass being amplified - so by doing that resistor thing to his woofer Kephart or Wiggins or wherever that quote came from impacted the response curve of the woofer.  The goal of doing this is to make the 'Q' as flat as possible while maintaining respectable output.

I'm assuming (i'm not going to take the time to read the paper, which you can find on web-archive.com, for this quick response)  that whoever was doing that was demonstrating a neat way to edit out a peak in an otherwise peaky woofer system.

This isn't really relevant for you because the 10w6 is an extreamly 'flat' response curve - meaning it isn't peaky at all when left to itself - you'd have to introduce eq'ing or design a box to induce a peak in the response of that particular woofer.

Anyway - I'm making some assumptions about your system, so you should be a bit more descriptive as far as what you like and don't like about your system, include more information about your system, like box size and type, amplifiers used, and such - and I (and the rest of us) could be lots more help.

Anyway, I think the last thing anyone other than an extreme "power user" should be trying to tune a system using resistors between vc's.