Radio Design Labs ST-PA6 6w Mono Audio Amplifier ‐ 8 Ω - Economical Power! This Mono Audio Amp offers 6 watts of power for a price you would expect to pay for 3 watts! Including two balanced audio inputs, a gain control, equalization control and an 8 Ω output. The output is designed to deliver a clean 6 watts RMS into an 8 Ω speaker.