Headphone Amplifier Module. Features: Serving up both balanced and single-ended flavors-AM3ALess ThanbRGreater ThanThe AM3A is an all-new amplifier module with both single-ended and balanced headphone outputs. It uses the widely-acclaimed AD8620 precision, wide bandwidth JFET operational amplifier as well as the tailor-made OPA926 op-amp, which was exclusively designed for the X7 and X7 Mark II. Using the screwdriver included in the accessories of X7/X7 Mark II to unscrew the T5 screws and exchange the headphone amplifier module. Although protection circuits are installed on the X7/X7 Mark II, it is still recommended to perform module exchange while the unit is turned off. Connectivity: 2.5 mm TRRS and 3.5 mm headphone out jack. Compatibility: FiiO X7/X7 Mark II players.