Output Sets
Output Sets is the number of complete stereo signal outputs provided by a tonearm. Each set carries the left and right channels.
One left/right RCA pair is one set, not two. A ground terminal does not add a set. Neither does a cable offered with a choice of RCA or XLR plugs: alternative terminations are different ways to connect one output.
Output Sets — Tonearm
Check the actual supplied wiring, whether the arm is sold separately or fitted to a turntable. Bi-wiring uses two sets of signal wiring; an optional version is not necessarily supplied. More sets offer connection choices, not a sound-quality rating.
The output connects to a phono stage, which amplifies the cartridge signal. Two sets do not automatically permit using both at once. Check the arm or turntable and phono-stage makers’ instructions for simultaneous connections, cartridge loading (the electrical load on the cartridge) and grounding before connecting both.