A small headphone amplifier with DAC built in with a variety of digital/analog inputs. Not only can it be used as a DAC+ headphone amplifier, it also works as a single DAC, headphone amplifier alone, or USB sound card, so it can be used in a variety of environments. DAC sections and opamp sections are independently placed by LR The L-channel and R channels are individually driven to deliver ultra-high resolution and impressive sound quality. Equipped with an abundance of input systems: USB, optical, coaxial, and analog stereo. It is also an excellent DAC device. Equipped with 2 outputs (only in digital input) and headphone output. A luxurious vertical brushed black housing that has been hand finished one by one by one artisan. Built-in lithium polymer rechargeable battery, can be used for a maximum of 30 hours on a single charge (about 6 hours). Maximum time when using headphone amplifier only. Up to 18 hours when using DAC+ headphone amplifier. Battery life varies depending on the environment used.