Amplifiers or receivers that use a high current design in the power amp section work well with Polk loudspeakers and generally sound better. Unfortunately, electronics manufacturers do not publish the current capabilities of their products. The best way to determine whether a given model is high current or not is to look at the wattage specs. High current models have much higher wattage ratings into 4 ohms than into 8 ohms. If there is also a wattage rating for 2 ohms which is higher than for 4 or 8 ohms, so much the better.