The Topping D50s Desktop DAC is a converter for many digital signal sources. USB (Universal Serial Bus) coaxial & optical inputs can all be sent through the dual DAC circuitry in this device. What makes this a step up from the lower-priced products in Toppings range is the high-quality Bluetooth receiver which you can connect to with your phone. D50s supports up to 384k Hz PCM as well as DSD at 256 bits. With this range you can listen at whichever quality you may own music without any loss of fidelity. The D50s is a very simple addition to your setup. Simply plug the device into your mac or pc with no additional drivers required. Additional software is required for playing the highest quality files. The D50s has a preamplifier function built into the unit allowing you to connect to power amplifiers or speakers with little to no noise. For those who are more technically inclined the OP amp can be swapped for a different tone from your DAC.