Subwoofer/monoblock connection

Any way you like. I use spades. This leaves the banana connector free. For a while I twisted bare wire and stuffed it in the banana hole. You could also twist bare wire around the bare part of the spade connector. Really. Does. Not. Matter.

Put these two together and it means all you have to do is connect +/- to +/-.

Caution!!! Some amplifier (bridged amplifier and some class D amplifier) are not safe to connect to subwoofer via high level (speaker level) +/- to +/- connection.

What monoblock amps that you like to connect to the high level inputs on a pair of subwoofers?

Yeah, if the amps are balanced (differential) you cannot simply wire + to + and - to -. The REL method is one sub to each amp, using whatever connection method you wish. (I use bananas with spade speaker connections) If balanced, simply leave the negative lead disconnected. If there is hum, ground this lead to a chassis ground. Some amps, such as Pass, provide a ground post for just such a connection. If you still have hum you will most likely have to use the low level inputs from a pre-out or Sub-out on your preamp. IF your amps are not differential amps, your connects are as Miller states.

IF your amps are not differential amps, your connects are as Miller states.