A headphone amplifier is simply a miniature power amplifier specifically designed to drive the tiny speakers inside headphones.
Headphone amps are most useful with certain power-hungry high-impedance audiophile headphones that can benefit from the improved clean power of a dedicated amp. A headphone amp can improve detail resolution and dynamic range extension and maximize overall musical clarity.
Because headphones are often used with portable devices, some headphone amps are battery-powered for use on the go.
Some headphone amps also include built-in digital to analog converters (DACs) with a USB or optical port to connect directly with a laptop, PC or tablet, as well as optical and coaxial connections for compatibility with other digital audio sources.
Just like a good speaker, good headphones can benefit from the clean power of a headphone amplifier to sound their very best.
Most good headphones can be improved with amplification, but a few absolutely require a headphone amp to perform well.
A DAC (Digital to Analog Converter) will turn your computer or other digital-output audio device into beautiful music.