P1

Perfect · 0 semitones

Unison

Two identical pitches played together or in sequence. The foundation of pitch — any two notes in unison are the same frequency.

perfect0 semitonesP1

How to Hear It

How to Identify It

Unison sounds like a single note with no movement. It has no tension and no sense of direction. Listen for the complete absence of any interval quality.

Famous Examples

  • Unison singing or playing in an orchestra section
  • The opening note of any melody before it moves
Ready to test your ear?The recognition trainer plays random intervals — identify them by ear with instant feedback.
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Often Confused With

All Intervals

About the Unison

The Unison (P1) is a perfect interval spanning 0 semitones. Two identical pitches played together or in sequence. The foundation of pitch — any two notes in unison are the same frequency.

To train your ear to identify the unison reliably, practice hearing it in all three modes — ascending, descending, and harmonic. The ascending version is most commonly tested, but recognising it in all contexts is the mark of a trained ear. Use the trainer above to test yourself in a mixed set of all intervals.