Wiring a D4 ohm and D2 ohm subwoofers together to 2 ohms?

[MrLandedra]

Just a question a friend had asked me, and I honestly don't know the answer. I told him I would find out and let him know tomorrow, so the question is: Can you wire a Dual 4 ohm AND a Dual 2 ohm subwoofer to the same amp and have it come out to 2 ohms?

If so, what are the risks, and if you can't, what's the cause behind it?

[truthsayer]

No you can't get a 2 ohm load with the subs you have. Either .666 ohm parallel or 12 ohms in series.

[OrionStang]

So much fail.

One sub will see more power than the other, it just doesn't work right.

[CleanSierra]

The parameters of the sub are actually different as well, not JUST the voice coil impedance. The other T/S specs are different between a D2 and D4 of the same sub.

[S15_Silvia]

Ok, look:

I'll use the rightmost formula in the blue section. P = (V^2)/R. At a given voltage output from the amplifier, the speaker with a smaller R will consume more wattage (P). This (and the different T/S parameters as mentioned) is why wiring different-impedance drivers to the same circuit is a bad idea.

Another edit: TECHNICALLY speaking, it's possible to run just one coil on the 4Ω sub and put the 2Ω coils in series on the other sub, then parallel that all together. DON'T DO IT, but theoretically it can be done. I am not responsible for damaged subs.

[MrLandedra]

Thanks guys, I'll let him know.

[k58.cross]

I am necromancing this thread.

I have a dvc 2 ohm and dvc 1 ohm sub of the same make/model. According to the manual the t-s params are essentially the same for both subs. I could get a final 0.7 ohm load by wiring the dvc 1 ohm coils in series to make 2 ohms, then that in parallel with the other 2 ohm coils (so parallel combo of 2:2:2). If I did this and put them in a 2x12 box I already have made and power from a monoblock that I know can handle the load, will it work or will I get cancellations?

I know there's statements such as "they will get different power", but can I get the info from someone who has tried this or knows someone who tried it?

I did do something similar in the past. Two Type-R 12's which were one generation apart. They were the same DVC 4 ohm, but different physical constructions altogether so the t-s params had to be different. I had no issues pounding the shit out of them.

[Joshdashef]

19 minutes ago, k58.cross said:

I am necromancing this thread.

I have a dvc 2 ohm and dvc 1 ohm sub of the same make/model. According to the manual the t-s params are essentially the same for both subs. I could get a final 0.7 ohm load by wiring the dvc 1 ohm coils in series to make 2 ohms, then that in parallel with the other 2 ohm coils (so parallel combo of 2:2:2). If I did this and put them in a 2x12 box I already have made and power from a monoblock that I know can handle the load, will it work or will I get cancellations?

I know there's statements such as "they will get different power", but can I get the info from someone who has tried this or knows someone who tried it?

I did do something similar in the past. Two Type-R 12's which were one generation apart. They were the same DVC 4 ohm, but different physical constructions altogether so the t-s params had to be different. I had no issues pounding the shit out of them.

Wouldn’t recommend it if you want your equipment to last. Cheaper to sell and buy proper drivers than go through the hassle of destroying equipment imo

[k58.cross]

Why is there risk of destruction though? I'm trying to ask for a technical explanation of what happens. Like here I will try to use some logical deduction:

* Assume subs are completely in phase, because time delay between the two can lead to cancelling waves.

* Two 2 ohm coils will get the same voltage as the series-combo of the 1 ohm coils, since all is in parallel. However, the two series 1 ohm coils will split the voltage they get. BUT since those coils are physically fixed to each other, shouldn't that split voltage combine back up anyway?

* As long as the subs are in phase and cone displacement is roughly the same, there should be no electrical or mechanical opposition between the two subs and output will be normal.

* IF one sub has different cone displacement than the other, will that negatively affect operation? This question goes into fluid dynamics I think, because you're dealing with air compression systems both in a chamber and in "open space".

 

I'm looking for answers beyond people just saying it's "common knowledge". I kinda think people are just going off of what each other has been saying for awhile, which doesn't necessarily make it an absolute truth.