How to hook up speakers

I'm pretty ignorant folks. Usually I hook up the black and red speaker wires to the black & red inputs. I haven't a clue which goes to the O & H screw lugs on the back of the Scott 340-B my mom gave me.
Fair question; not a sign of ignorance, as things were often labelled differently in those days than they are today.

Assuming that the Phase switch on the rear panel is set to Normal, O = Black, and H = Red.

There won't be much if any difference if BOTH channels are reversed from that. If only one channel is reversed from that, however, the sound would be very poor, but setting the Phase switch to Reverse would correct it.

To be sure it's clear, the O and the H that are marked on the rear panel refer to the bottom row of screw terminals, which is where the speakers are connected. Two wires that emerge from the rear of the unit (one for each channel) are connected to the upper row of screw terminals, to whichever pair of terminals (one terminal for each channel) correspond to the impedance of the speakers that are being used (4, 8, or 16 ohms).

You can find a pdf of the manual for the 340B at, provided that you register there.

-- Al