Single-channel vintage-style compressor with signal path that utilizes only discrete components like resistors, capacitors and transistors. Its line input and output are transformer balanced and the unit also has a third inter-stage transformer. The compressor uses a diode bridge as the gain control element, a method that is revered for its smooth way of operation. Some of the most sought after vintage compressor designs, like the 2254, 2264, 33609, Siemens and EMI used the same basic design. The controls are very flexible covering broad ranges of Ratio, Attack and Release times, including two Auto positions. All controls except the Gain make-up one are stepped for easy resetting and stereo matching. There are three selectable side-chain high pass filter frequencies available to handle special situations. The Bypass switch is a true bypass where a relay switches the complete circuitry in or out. The IN/OUT switch makes it possible to switch the compression on and off while retaining the colouring from the transformers and the electronic circuitry. The meter can show output level or gain reduction. It is also possible to link two units for stereo operation. The compressor uses external power supply to avoid interaction with the audio circuitry and the transformers. A 230V power adaptor is included.