Headphone Power Calculator

Headphone impedance, measured in ohms, represents the opposition to current in AC circuits. Higher impedance headphones (over 100 ohms) generally require more voltage to reach the same volume and often benefit from a dedicated amplifier. Lower impedance headphones (under 32 ohms) are typically easier to drive from portable devices.

You may need a headphone amplifier if your headphones have high impedance (above 100 ohms), low sensitivity (under 90 dB/mW), or if you find yourself maxing out the volume on your current device without getting sufficient loudness.

Headphone sensitivity, also called efficiency, measures how loud the headphones will play at a given power level. It is typically expressed in dB SPL/mW (decibels of sound pressure level per milliwatt) or dB SPL/V. Higher sensitivity headphones produce more volume with less power.

It depends on the sensitivity. A pair of 250 ohm headphones with high sensitivity (over 98 dB/mW) may work adequately from a powerful laptop or audio interface. However, most 250 ohm headphones benefit significantly from a dedicated amplifier to reach their full potential.