Amplifier, power and impedance

An amplifier supplies voltage and current to a driver. Loudspeaker impedance changes with frequency and includes phase. An 8 Ω label does not mean an eight-ohm resistor across the entire band.

Read power ratings together with load impedance, distortion and measurement conditions. Overdrive may clip the signal. Use a speaker load supported by the amplifier; a larger wattage figure alone does not guarantee better sound.