Vox amPlug Metal Guitar Headphone Amp Available in three styles: VOX AC30, Classic Rock, and Metal. AUX in jack lets you jam along with your CD/MP3 player. 100% analog circuit faithfully simulates the response of the original amps. AC30 emulates the AC30 top boost sound of a vintage VOX AC30. Classic Rock gives you the great high-gain sound of a UK-made 100W amp.