Primary tone
[Image:Ursatz 321IVI revised.png|thumb|right|150px|The minimal fundamental structure. Primary tone:.
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In Schenkerian analysis, the primary tone or head tone is the starting tone of the fundamental line. The fundamental line itself originates as an arpeggiation of the tonic chord, filled by passing tones:
The primary tone therefore necessarily is one of the higher tones of the tonic chord,, or.
The fundamental line descends from its primary tone to the tonic, :