]Can I wrote:
convert a 2ohm sub to a 4ohm sub or visa versa with just wiring.
No
]  wrote:
I have 2 4ohm subs and 1 2 ohm subs. Both are Alpine Type Rs and both are dual voice coil.
Both? Are all three subs dual voice coil? As in, two are DVC 4 and one is DVC 2?
If so, series-wire the coils of each sub (one coil's positive to the other coil's negative). The DVC 4 ohm subs will each be 8 ohms and the DVC 2 sub will be 4 ohms. Then use a wire and connect one positive of each sub together and then to the amp pos. terminal. Another wire links one negative of each sub together and then on to the neg terminal on the amp. You will have a series / parallel wiring scheme.
This will provide a 2 ohm impedance. You must use a class D mono amp to power this trio. Don't connect this load to a bridged stereo amplifier, whether it implies "mono" or not. This wiring scheme would fit your criteria of being "somewhat stable" because the odd sub, of course, will receive twice the power as either of the twin subs.
https://www.the12volt.com/caraudio/boxcalcs.asp
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