The Golden Ratio Phi V2 is a compressor pedal with an all-analog circuitry that has been upgraded from the original model. Equipped with three completely independent compression circuits in a compact housing, this single unit covers the sounds of everything from vintage pedal compressors to legacy studio rack compressors. The built-in "headroom switch" can boost the voltage to 18V, ensuring greater headroom while maintaining low noise. ●FET: A sound mode with a fast, fat, and aggressive response reminiscent of the legendary rack compressor "1176." ●OTA: A dynamic and versatile sound mode reminiscent of the vintage "Ross Compressor" and "Dyna-Comp." ●OPTO: A sound mode that uses carefully selected photocells to obtain a natural response according to the strength of the input signal. Internal controls ●FET Compression circuit Ratio/Distortion Trimmer: Allows you to adjust the gain and compression ratio in FET mode when using a high-output guitar or bass. ●HEADROOM Switch: Can boost DC9V to DC18V. When 18V is selected, the headroom increases. ●OUTPUT Switch: Allows you to select the output gain level. In "H" mode, it is boosted by 8db.