well sorry but a DVC 2ohm wired in series gives you a 4ohm load not a 2ohm load, so if you need to go to a 2ohm load either a svc 2ohm or a dvc 4ohm or a dvc 1ohm in series. I'd go here if you need to learn about wiring a sub in different configurations
No, you got me wrong, i mean does it make a difference if you get a DVC 4 ohm wired with the VCs **parallel** (not series), for 2 ohm stereo stable amps, or could i go with a DVC 2 ohm sub and only wire one voice coil for the same amp, or is it hard on the sub not to use both VCs..
He is talking about wiring it stereo I believe. 1 vc to one chan and the other to the other chan? If this is what you are talking about then yes you can run a dual 2ohm coil to a 2 chan 2ohm stereo stable amp.
you can certainly only wire one vc on a dvc sub. while the field produced from powering both vc combines to form one net force driving the cone forward, pushing one vc simply pushes the driver with half the power. also, the sub will have an increase in Qts (peakier resonance). since the sub wasn't intentionally designed to have this effect, you will likely not like the results. but there are/can be advantages. if you were to place a resistor on that open vc, you could adjust your Q with a knob. a useful option to some. regardless, there is no harm in running one vc. and yes, it would be driving the sub at whatever impedence it has per-vc (since you will be running only one vc).
like Mike said a resistor is required and thats something that most don't do. I believe AA has it on their high end subs IIRC but wiring just one VC without a resistor can cause problems. Too many times have i read and heard stories of shops like CC or BB doing that and messing people up. Also i don't think most companies will warrant any problems if wired in this manner, but i'd check before you do it.
this isn't with concern to damaging the speaker so much as it is to the resulting lack in performance. again, you will only be driving the sub with 1/2 the power which typically results in a 3db drop in output. then, as stated, the Qes rises.
"If you HAVE to use only one VC, then short out the other one."
there is a reason there are 2 vc's, it is always better to use the equipment for how they were built to run. the best thing to do is find your amp that you want to run or have and then match subs up to that.