How to choose amp for headphones

1. How do I know if my amp is powerful enough for headphones?
2. Do headphone amps affect sound quality?

How do I know if my amp is powerful enough for headphones?

Purely considering power, you need to look at four specifications:

1. Headphone Impedance (ohms)
2. Headphone Sensitivity (dB/mW)
3. Amplifier Output Voltage or Power at your headphone's impedance (V or mW)
4. Amplifier Output Impedance (ohms)

Do headphone amps affect sound quality?

Adding an amp between the player and your audiophile headphones can provide a significant, audible improvement in clarity, detail and dynamics. ... So while low-impedance headphones may be loud enough from a portable device, sound quality can be significantly improved by adding a headphone amp.