The single, red PSI Audio A17-M is a classic powered near-field monitor designed to be tonally balanced, with high-resolution detail and an efficient transient response for accuracy in surround setups. The bi-amplifier delivers 80W to the 6.9" woofer and 40W to the 3.9" tweeter, which combine to provide a frequency response of 43 Hz to 23 kHz at an SPL of 115 dB per pair.