8ohm speakers

[jblayz1 10+ year member]

i have a question about 8ohm speakers. when setting the gains on the amp to these speakers, would you set to the speaker or amp? what i mean is, say you have 120rms 8ohm speakers and 120 x 2 @ 4ohm. would you set your gains to 120 x 8 (sqrt) = 30.9v or 120 x 2 (sqrt) = 21.9v ??

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[DejaWiz 5,000+ posts]

i have a question about 8ohm speakers. when setting the gains on the amp to these speakers, would you set to the speaker or amp? what i mean is, say you have 120rms 8ohm speakers and 120 x 2 @ 4ohm. would you set your gains to 120 x 8 (sqrt) = 30.9v or 120 x 2 (sqrt) = 21.9v ??

An amp that is rated for 2x120w rms with a 4 ohm load can not output 2x120w rms with an 8 ohm load, unless it's specifically engineered to do so. Figure about half the 4 ohm power when driving an 8 ohm load.

Square Root of (Watts * Ohms) = Output Voltage

...SQRT(60*8) = 21.9v