Parallel: Two sets of wires running from the + and - of the receiver to each of the posts on each speaker. So they run out as a Y.

Serial: One wire from the + of the receiver runs to the + of one speaker. A wire connects the - of that speaker to the + of the second. Last, the - of the second runs back to the - of the receiver.


Pioneer PDP-5020FD, Marantz SR6011
Axiom M5HP, VP160HP, QS8
Sony PS4, surround backs
-Chris