Ampeg OPTO COMP Analog Optical Compressor Bass Effect PedalThe Ampeg Opto Comp Analog Optical Compressor pedal utilizes an optical circuit to deliver smooth, vintage style compression to add headroom and sustain to your guitar or bass. Dial in a fast, subtle style to control peaks or crank up the compression to add a unique character. Featuring a roadworthy all metal chassis and true bypass switching, the Opto Comp Optical Compressor brings your tone to new heights. Features Delivers smooth, vintage style