The FiiO K5 Pro ESS is used as a link between a computer, music player, smartphone or tablet as input source and active speakers or headphones as output source. This way, you can easily create an uncomplicated and space-saving mini audio system. The high-quality ES9038Q2M digital-to-analogue converter from the ESS brand ensures very lifelike and dynamic sound quality. The built-in Texas Instruments headphone amplifier is a powerhouse and capable of driving just about any headphone. The XMOS XUF208 USB chip processes high-resolution data up to 768 kHz/32Bit and DSD512. This ensures that every single sound detail is reproduced with absolute realism. The many connection options make the FiiO K5 Pro ESS an interface for various audio equipment. A computer or notebook is connected to the USB input of the FiiO K5 Pro ESS. Music players, smartphones, tablets, etc. can be connected to the RCA inputs as well as coaxial or optical. RCA outputs are available for connecting speakers. Headphones are connected to the 6.35 mm jack on the front of the K5 Pro ESS. A 6.35 mm to 3.5 mm adapter is included so that headphones and earphones with 3.5 mm plugs can also be used. On the front of the FiiO K5 Pro ESS is a control for three gain settings, so that headphones with different sensitivities can be connected. Another switch can be used to switch between input sources (USB-DAC / LINE-IN / SPDIF (Optical/Coaxial). The large metal volume dial on the front of the K5 Pro ESS allows for precise and convenient volume adjustment. The solid aluminium housing of the FiiO K5 Pro ESS is kept in discreet black, compact in dimensions and fits just as well on the desk as in the HiFi rack.