#10, but with TRS plugs as drawn. If you use tip and sleeve, it shorts the low side of the amplifier to ground. when I got my tascam monitors with the stupid mono quarter-inch plugs to RCA pin plugs cable, the first thing I did was cut the quarter inch plugs off and install TRS plugs and left the low side floating.
Incidentally, absolute phase does not matter. So that means you can use the low side of the amplifier output and the shield, to feed another identical output to another set of monitors somewhere else. We used to do this frequently in the broadcast industry, where we had to feed two studios with one signal, and the console provided a balanced output.