Wiring in series or parallel

Running in parallel would result from sending the + output to the + in speaker 1 and the + in speaker 2. The - output would also be sent to both the - in speaker 1 and the - in speaker 2. This could either result from a) running two wires from the + output to the + of each speaker and two wires from the - output to the - of each speaker or b) running one wire from the + to speaker 1 and then running another wire from the + in speaker 1 to the + in speaker 2 (ditto on the -).

Running in series would result from sending the + out to the + in speaker 1. Run another wire from the - in speaker 1 to the + in speaker 2. Run another wire from the - in speaker 2 to the - output.

Running in parallel cuts the impedence in half so it might sound louder in the rear and the amp has to be able to handle and impedence that low (e.g., an 8 ohm impedence turns into a 4 ohm impedence overall). Running in series doubles the impedence so it might sound quieter in the rear but the amp should have no issues.

Wiring in series, take your speaker wire and connect the + side to the red speaker terminal of one speaker, the - to the black terminal on the other speaker. split one of the wires in half, or just use one side, but connect the - of your first speaker to the + on your other speaker. Whatever the ohms are for your speakers, they will now double. Example, one 4 ohm speaker in series with another 4 ohm speaker now presents an 8 ohm load.
Wiring in parallel, connect both +'s (red) together, both -'s (black) together. Now your ohms will be cut in half. Example, one 4 ohm speaker wired in parallel with another 4 ohm speaker now presents a 2 ohm load.
Simple, huh? Good luck!

By the way, if you go the series route, you can lower the overall impedence by slapping a resistor across the + and - outputs (make the resistor equal to two times the impedence of your speakers -- e.g., your speakers are 8 ohms so in series they are 16 ohms so you would need a 16 ohm resistor in in parallel across the speakers so the total load drops back to 8 ohms).

See this recent thread for some good suggestions on raising or lowering the impedences and the devices you can use:

http://forum.audiogon.com/cgi-bin/fr.pl?cspkr&1080863019&read&h12&zzlArj&&#rest

Good responses. Ozfly, I had forgotten the thread you listed. Very informative.