How to Power Two Speakers with a One Channel Amp

Speakers in Series

If you connect the speakers in series, you're adding the speaker impedances together. Example: You have two 4 ohm speakers you want to connect to an amplifier with an output impedance of 8 ohms. For this case, you want to put your speakers in series, so the total impedance of the speakers will be 4+4=8 ohms, matching the amplifier.

Plug the negative terminal (-) of the amplifier into the negative terminal of the first speaker.

Connect the positive terminal of the first speaker to the negative terminal of the second speaker.

Connect the positive terminal of the second speaker to the positive terminal of the amplifier.

Speakers in Parallel

For a parallel connection of two speakers, the resulting impedance is half of the impedance of the amplifier (assuming the speakers have the same impedance). Example: You have the same two speakers, but the amplifier has a 4 ohm output. For this case, you want to connect the speakers in parallel because the impedance would be 8/2=4 ohms, again matching the amplifier.

Plug the negative terminal (-) of the amplifier to the negative terminal of speaker 1.

Hook the negative of speaker 1 to the negative on speaker 2.

Plug the positive terminal (+) of the amplifier to the positive terminal of speaker 1.

Hook the positive of speaker 1 to the positive on speaker 2.