Headphone amp is an electronic audio device with low impedance. A headphone amplifier is used specifically to run headphones.
What does a headphone amp do?
It is a kind of a mediator between an audio source and a headphone. Having different impedances they won’t reproduce the sound as clearly as it is recorded for the difference of sound waves perceived and generated. A headphone amp is intended to increase the power of audio signal from the audio source with a low voltage like a mobile phone or MP3 player to make the headphones play the sound on a sufficient level. They convert the sound signal to the level that may be converted and reproduced with a decent quality by your headphones, raising their strength and making the music sound clearer and louder.
Embedded headphone amp
Usually, most audio devices with low impedance have an embedded headphone amp. This may be found in electronic appliances that are supplied with a headphone output, like mobile phones, portable audio players etc.
Separate headphone amp
Though, detached headphone amps are also represented and are used mostly by audiophiles and professionals for audio recording and critical listening. They are produced in a variety of types and may help to deliver much more sound quality and details from your devices that even have a built-in amp. That’s why separate headphone amps are more popular with professionals and music fans.
In general, a headphone amp helps to achieve a better quality of sound in headphones of any impedance connected to various devices making them more compatible.