An audio Y adapter is a cable with three ends. One end is common to split the signal to two ends. The audio Y adapter cable is a great way to split an audio signal. Choose from balanced or unbalanced versions. Cables can be used from a preamplifier into two amplifiers, or between an amp and a mixing board, or from one preamp to two subwoofers. Tributaries offer three types of Y adapter cables designed specifically for audio: Balanced XLR, Unbalanced RCA, and Portable Y with a 3.5mm mini stereo plug to 2 RCA.