The HP12U 12-Channel Headphone Amplifier with USB from AKG features two stereo input and six stereo output channels, each with two 1/4″ outputs. It can be used to easily monitor your analog or digital equipment – without rewiring your headphones – by switching between inputs A and B. Simply connect multiple units if you need more channels. In addition, the HP12U can also be used as an external sound card by connecting input A to your computer via USB. Housed in a sturdy chassis, the HP12U is an ideal headphone amplifier for any recording session.