Power amplifiers from $5,000 to $10,000 are built for speakers that demand serious current and for listeners who want full dynamic range at realistic volume levels. Output stages use premium transistors or tubes with thermal management designed for sustained high-power operation. Power supplies are massively overbuilt relative to rated wattage, which means the amp has reserves for musical peaks that lesser amps clip or compress. If your speakers have a reputation for being "hard to drive," this is the tier that tames them.