Both input and output are RCA interfaces, with one set of two-channel audio input and five sets of two-channel output, allowing connection to five power amplifiers or active speakers, featuring 3 times gain compensation amplification (9.5dB). Frequency range: 20Hz–20kHz Input impedance: 50k ohms Output impedance: 600 ohms Gain: 9.5dB This unit offers low noise and high fidelity performance, capable of stable long-term operation when powered on. Use a low-ripple power supply; the power interface is 5.5 x 2.1mm with center positive and outer negative polarity. Color: Black Material: Plastic and metal Package Contents: 1 x Tone Controller Only the above package content; other items are not included. Note: Light reflection and different display settings may cause slight color variations between the image and the actual item. Measurement allows an error of +/- 1–3cm.