To give the answer to the question whether amps improve sound quality we should understand what they really do.
One of the common questions with casual audio listeners is ‘Do I need a headphone amp?’. In fact, almost any audio device that serves as a source of sound and a headphone jack has an embodies amplifier. That is the detail that makes the headphones play perceiving and transmitting the signal of the source.
Headphone amp is an electronic audio device with low impedance. A headphone amplifier is used specifically to run headphones.