For optimal sound quality from your Hifi headphones, it is often a great idea to invest in a DAC or headphone amplifier, as the sound quality from a computer's or telephone's analog audio output is often limited. When using an USB DAC, the device will take over the function of the computer's, usually economical, sound chip and deliver the sound quality that the headphones can utilize. In addition, the head amp often also offers some advantages in user-friendliness, e.g. manual rotary knob for volume control, high-quality Bluetooth reception, etc.
– See the selection of headphone amplifiers