Check the listing for details. KORG GEC3 Student Interface Audio Unit (WTF87). Condition: Used. Listed at 7.50 USD. The KORG GEC3 Student Interface Audio Unit is a MIDI interface specifically designed for musicians and producers looking to create high-quality music compositions. This unit, powered by Korg, offers 2 line inputs for connecting various audio sources. With a compact and user-friendly design, this audio unit is perfect for students and professionals alike who need a reliable and versatile tool for their music production needs.