This External USB sound card based on the high quality Burr-Brown (Texas Instruments) chip PCM2906. The card has a line input and a line/headphone output. The signal is filtered with the active band-pass filters, realized with the high-performance Burr-Brown OPA2353 low noise opamps. The used capacitors are tantalum electrolytic capacitors from "Kemet". The card has 3 control buttons: "Volume up", "Volume down" and "Mute". It has also SP/DIF interface - external DAC can be used for the digital to analog conversion. In this case the card wil work only as USB codec, and the DAC will produce the audio signal. The card does not need a driver from Windows XP, Vista and Windows 7. It can work also under Linux - but must have a USB driver installed.tested also under macOs Mojave (Ver. 10.14.6) - works without problems. This card is nice solution if your computer does not have working audiocard, or its performance is unsatisfactory.