[Cohibaman]

Originally Posted by audio bill

Here's a quick primer on how power delivery works with conventional (non-transformer coupled) solid state amps. Power is calculated as voltage times current. The amp essentially delivers a stable voltage output dependent upon the signal level, but lower impedance speakers draw additional current. So for example a 4 ohm speaker draws twice as much current as an 8 ohm speaker which effectively doubles the power output. This is the ideal situation if the amp's power supply can source adequate power, if not the amp may reach its current limitation sooner such that the power cannot double as you halve the load impedance. Hope this helps!

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