Gyraf Audio Gyratec G22

Stereo/Dual/MS Compressor Manufactured in Denmark, the Gyraf Audio (pronounced "giraffe") Gyratec XXII, or G22, is an enhanced version of the company's popular G10 stereo Vari-Mu tube compressor that preserves the all-tube, transformer and passive-component audio path. In continuous use, I found the unit only gets slightly warm on the top cover's rear quadrant, which bodes well for installing the unit into a tight rack without worry. Besides the main board with its solid-state power supply and voltage regulator circuitry, there is also a large toroidal power transformer mounted at some distance on the other side of the cabinet. Each channel uses all Class-A double-balanced topology with a PCC-189 (7ES8) remote cutoff dual triode differentially driving an ECC-88 (6DJ8) dual-triode output stage. The side-chain/control section uses TL074L quad op-amp chips for deriving threshold, attack and release timing, compression ratio, Vari-Link and the HPF.