Technics SH-3040 Headphone Ambience Controller ヘッドホンアンビエンスコントローラー Some scratches and dirt are present. The following is quoted from Audio-Heritage: (https://audio-heritage.jp/TECHNICS/etc/sh-3040.html) An ambience controller that is a sister model to the SH-3045. When combined with the EAH-300, EAH-320, EAH-520, and EAH-510, it creates depth and a sense of spaciousness in the playback sound of headphones. Type: Ambience Controller Frequency Response: 20Hz～20kHz Distortion: Less than 0.3% S/N Ratio: More than 60dB Input Impedance: 1.5kΩ Optimal Load Value: 125Ω Power Supply: AC100V, 50Hz/60Hz Power Consumption: Maximum 3W External Dimensions: Width 114x Height 82x Depth 190mm Weight: 1.3kg