Both input and output are RCA interfaces. One set of two-channel audio input and five sets of two-channel output allow connection to five power amplifiers or active speakers. Features 3 times gain compensation amplification (9.5dB). Frequency range: 20Hz20kHz Input impedance: 50k ohms Output impedance: 600 ohms Gain: 9.5dB Low noise and high-fidelity performance with stable long-term operation when powered on. Use a low-ripple power supply. Power interface is 5.5 x 2.1mm, center positive and outer negative. Color: Black Material: Plastic and metal Package Contents: 1 x Tone Controller Note: Other products are not included. Light reflection and display differences may cause slight color variations between the image and the actual item. Measurement error allowed is +/- 13cm.