What size amplifier for 100w speakers?

For 100-watt speakers, a good rule of thumb is to use an amplifier that can deliver about 75-150% of the speaker's power rating. This means you should look for an amplifier with a power output of 75 to 150 watts per channel at the speaker's impedance rating (usually 4 or 8 ohms). This will ensure that the amplifier can drive the speakers effectively without distortion, especially at higher volumes. Consider your listening habits and the size of the room as well when selecting the appropriate amplifier size.