ART Powermix III - compact 3-channel mixer, accepts either mono or stereo signals and mixes them down to stereo or identical L/R mono signals, headphone output level control. Maximum gain: +27dB, input impedance: 10kohms, maximum input level: +30dB, maximum output level: +13dB, output impedance: 100ohms, total harmonic distortion: >0.005%, includes 12V DC power adapter. Dimensions: 143 x 92 x 45mm. Weight: 590g