I'm using a REL sub with Bryston monoblocks.
I have the main speakers connected via spades to the amps, and the sub is connected to the same terminals via bananas -- running through the high pass on the sub. The sub's ground was connected to the chassis of one of the amps, then (on advice from one who knows) I connected the ground to an unused speaker connecter on one of the amps.
I don't know what the Rowland has for speaker terminals, but if it has typical 5-ways, you may try my setup.
Good luck,
Rich
I have the main speakers connected via spades to the amps, and the sub is connected to the same terminals via bananas -- running through the high pass on the sub. The sub's ground was connected to the chassis of one of the amps, then (on advice from one who knows) I connected the ground to an unused speaker connecter on one of the amps.
I don't know what the Rowland has for speaker terminals, but if it has typical 5-ways, you may try my setup.
Good luck,
Rich