Tube guitar amplifier head. The original JCM800 2203 changed the face of modern amplifiers forever. Updated and enhanced, the Studio Classic SC20H is here to do it all over again. Replicating our first amp that truly embodied the overdriven sound of heavy rock, the portable SC20H brings timeless sounds to the modern guitarist, with the option to switch between 20 W and 5 W at the flick of a button.