I've seen a few different ways to wire a DVC sub

in parallel. but which way is right?

Here are a few diagrams that I have found online:

Everything Car Audio: Single DVC Subwoofer wiring

Subwoofer Wiring Diagrams, One 2 ohm Dual Voice Coil (DVC) Speaker

Are either of these ways right or wrong?

Any help is greatly appreciated.

second link, first option

Edit: Why did you ask this is Fi's section?

second link, first option

Is wiring it the first way gonna reduce the load on the amp?

Making it a 2 or 4 Ohm load.

lower ohm of resistance => the more the amp/your electrical has to work

If you have a dual 2ohm sub make sure you're amp is stable down to 1 ohm. If so that would be more of a load on the amp but produce more power. If youre amp is not 1 ohm stable wire it in series would put less of a load on the amp but produce less power.

If you have a dual 2ohm sub make sure you're amp is stable down to 1 ohm. If so that would be more of a load on the amp but produce more power. If youre amp is not 1 ohm stable wire it in series would put less of a load on the amp but produce less power.

I have a Rockford Fosgate T2500.1BD and I have it

wired like the first diagram I displayed.

Is that an actual 1 ohm load?

If you have a dual 2ohm sub make sure you're amp is stable down to 1 ohm. If so that would be more of a load on the amp but produce more power. If youre amp is not 1 ohm stable wire it in series would put less of a load on the amp but produce less power.

I have a Rockford Fosgate T2500.1BD and I have it

wired like the first diagram I displayed.

Is that an actual 1 ohm load?

Yes!