Headphones

Headphone impedance

TL;DR

Headphone impedance ranges from 16Ω (portable-friendly) to 600Ω (studio reference). Higher-impedance headphones need more voltage from the amp to reach the same volume. Match your headphones to a headphone amp with adequate output.

Headphone impedance is the electrical resistance your headphones present to the amplifier. Ranges from 8Ω (some IEMs) to 600Ω (Beyerdynamic DT 880/990 Pro 600).

Impedance ranges

  • 16-32Ω – portable / phone-friendly. Any device drives them.
  • 50-100Ω – need a dedicated headphone amp for full potential
  • 150-300Ω – benefits from a proper desktop headphone amp
  • 300Ω+ – needs a purpose-built high-voltage amp (Beyerdynamic DT 990 Pro 250Ω is on the edge)

Matching an amp

Look for the amp’s output impedance and current/voltage rating. The AIYIMA H4 is a dedicated headphone amp for demanding cans; the FiiO K11 drives most 32-300Ω headphones cleanly.

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