Recreation of one of the most coveted audio valve compressors of all time, the legendary EMI/Abbey Road RS124. 6BC8,6CG7, 6AL5 Tube Circuitry Custom-wound Balanced Transformers Mono Channel Controls included: Input: Variable, Output Attenuator: Variable Attack: Selectable, Stepped (9 settings, including 3 Abbey Road Historic serial numbers), Recovery: Selectable, Stepped (6 settings, and HOLD), SuperFuse (switchable mode) Switchable 200/600 ohms Output Impedance Standard units come with variable Input and Output control. Stepped Input and Output controls are available via special request for an additional fee. Dimensions: 2U