This is the long-awaited compressor from JOYO R series. Features 2 knobs for INPUT/OUTPUT. You can adjust the output down when you turn on the compressor to finely adjust the volume level. GAIN REDUCTION Attack sound is displayed on a level gauge for greater visibility. The 3 adjustment knobs of RATIO/ATTACK/RELEASE/allows you to adjust the compressor to adjust the compressor according to the guitar that plays the richness of attack. Perfect for electric guitars and electric accos.