Wiring speakers in parallel yields lower impedence. In your case, 6+6 will equal a 3 Ohm load. Wiring them in series will add the load giving 12 Ohms. Your amp will probably be rated at some wattage at 8 Ohms and some greater wattage at 4 Ohm per channel if it's stereo. Some amps can also be bridged which changes things again... That's why I was looking for specs on the amp too.

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-Evan


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