3 dvc@4ohm amplifier suggestions

Three 10" DVC 2 ohm subs, right?  Add up the continuous power handling of 400 watts each...equals 1200 watts.   You could use an amp that outputs 1500 watts at a 1 ohm load, but it all depends on the enclosure.  Is it big or small or sealed or vented, or what?  You're most likely using sealed for those, am I correct?  If the enclosure is built to the recommended specs then any output at 1 ohm from 1000 to 1500 watts would be fine.  You could even go less, but when you are using three subs I doubt that less is what you want, especially with such a low impedance load on the amplifier (which is not the cleanest power you can get).

Strange sig line, my friend.

Wire the subs in series / parallel to yield a 2.67 ohm load. How on earth you are magically getting 1.3 ohm with 3 drivers I have no idea. Remember that all drivers must be wired in the same fashion or one driver will receive more power than the other. Find yourself a class D mono amp that is designed and engineered to operate at either 1 ohm or 2 ohm. I would try and find a older Rockford BD1000 series amp for this application as most of them put out more than 1100w rms into 2 ohms. It would be a good match. After that you will need a monster 1 ohm amp and pay close attention to the 2 ohm power ratings on it. The Concept CD2410 might be good in this application.

Wiring Option #1