Please help me not make a dumb mistake

I am putting together a new secondary system. Among other things, I am planning on hooking up a Rhythmik F12G subwoofer using the subwoofer's SPEAKER level inputs. On the Rhythmik website, its says:

"Our speaker level inputs are only compatible with power amplifiers having single ended outputs with black lead output labelled as "COM", "GND", or "Ground". Wyre4sound power amplifiers and others with differential outputs are not compatible."

The amplifier I would like to hookup to the subwoofer is a Prima Luna Dialogue 4. The Prima Luna's black lead outputs are not labelled "COM," "GND," or "Ground." They are labelled 0 Ohm. Is that the same thing as ground?

In other words, can I safely hook up the F12G subwoofer to the Dialogue 4 amp using the subwoofer's SPEAKER level inputs?

Thank you.

It will work fine. If you are super worried then call PL. Or even better simply remove the bottom cover and look inside. There you will see it is wired the way cleeds said, everything connects to the same ground. Tube amps are not crammed with lots of parts it will be easy to follow the wires, and see the - for both channels connects to the same ground. 

Ozzy62-- As you said, I have heard many people report that speaker level inputs can result in a more seamless integration. I hope that turns out to be true in this system. In the past, I have spent many hours trying to get subs to integrate using the low level inputs. I have sometimes achieved good results with the help of digital EQ and experiments in room placements. In this system, I will have no EQ capability and only a little latitude with room placement.

Cleeds-- Thank you for the good advice. I have reached out to the manufacturer and am waiting to hear back. I'm feeling more confident that it won't be a problem given russ69's experience. 

Russ69-- Thanks for your comment. It sounds like it will work fine.

I appreciate the help folks.