Subwoofer works in series but won't work in parallel?!?!? Please Help

[divebombvt]

Need help. A 15" Soundqubed sub, dual 4 ohm..... It worked fine wire in parallel, took it out, hooked it back up and it wouldn't work. Check coils they read 4 ohms each. Tried wiring it in series and it works. Tested wiring up an identical sub by itself and it works fine in both parallel and series. The only way to get the bad sub to work in parallel is to wire it together with the good sub in an odd way. I'll include a picture to describe how I got it to work. Need help, nothing is making sense, the sub just wont work by itself in parallel, but it does in series. And it will only work in parallel with a second sub if it is wired exactly as it is shown in the picture. If it is wired with jumper wires from each coil on the bad sub it stops and the good sub is the only one that works. Any ideas? http://s1195.photobucket.com/user/mlgudead/media/Audio/Subhelp.jpg.html

[Dan2427]

[Triticum Agricolam]

I'd try wiring up each coil individually and test to see if you can isolate the problem.

[Nightshade]

Check each coils impedance to make sure one is not open or fried. This is a reason for a sub to work under one configuration and not another.

[divebombvt]

I'd try wiring up each coil individually and test to see if you can isolate the problem.

Each coil works by it self, and reads 4 ohms by itself.

[divebombvt]

Check each coils impedance to make sure one is not open or fried. This is a reason for a sub to work under one configuration and not another.

Each coil reads 4 ohms on their own and read 8 ohms when in series. Wired to parallel ++ , - - , by itself it reads 0 ohms.

[Nightshade]

Check each coils impedance to make sure one is not open or fried. This is a reason for a sub to work under one configuration and not another.

Each coil reads 4 ohms on their own and read 8 ohms when in series. Wired to parallel ++ , - - , by itself it reads 0 ohms.

Hmm should read 2 ohms when wired in parallel. Something is fishy but without seeing it right in front of me I can't say. Have you tried playing it free air at low volume in parallel and seen what it does? Maybe try that and try moving the speaker wire to see if its not making connection somehow.

[divebombvt]

Check each coils impedance to make sure one is not open or fried. This is a reason for a sub to work under one configuration and not another.

Each coil reads 4 ohms on their own and read 8 ohms when in series. Wired to parallel ++ , - - , by itself it reads 0 ohms.

Hmm should read 2 ohms when wired in parallel. Something is fishy but without seeing it right in front of me I can't say. Have you tried playing it free air at low volume in parallel and seen what it does? Maybe try that and try moving the speaker wire to see if its not making connection somehow.

I have had it out of the box to try wiggling tinsel leads, the push terminals etc. Something must be shorting out inside the coil but it is weird how it would happen just from unhooking it then hooking it back up. Also the woofer hasn't seen more than 325 watts clamped, oscoped clean as can be. Still on break in, it's a 1200rms woofer. Something must've been defective is the best thing I can come up with. If you have more ideas though it would be really appreciated, I am at a loss here.