Tempo primo
Back to the piece's opening tempo.
What it means
Tempo primo means “first tempo” and calls for a return to the beat with which the movement began. Abbreviated it appears as tempo I or tempo 1. Equivalent are phrases such as tempo I<sup>mo</sup>.
The difference from a tempo is important and often overlooked. A tempo restores the tempo that applied immediately before the last change — that can be an intermediate tempo. Tempo primo, by contrast, reaches back across all intervening tempos to the opening tempo. In a movement that has proceeded from the opening tempo through several stages, the two markings therefore lead to different goals.
Related are markings such as tempo I<sup>mo</sup> ma più tranquillo, which invoke the opening tempo while modifying it at the same time.
In the notation
The marking stands in italics above the staff at the point from which it applies, and holds until a new tempo marking. It typically appears after a middle section with its own tempo or after a sequence of tempo changes. Some editions repeat at this point the original tempo word or the metronome number, which makes the intention unambiguous.
Musical use
The classic place is the return of the first part in three-part forms: after a contrasting middle section, theme and tempo return together. The marking also often stands at the beginning of a coda, when a movement finds its way back to its starting point after tempo changes. In works with many tempo changes it is the reliable means of establishing order.
It is notated as Tempo I.
Performance practice
Impress the opening tempo on yourself consciously before you begin the movement — it is the reference point to which you find your way back later. Take it at that point immediately and completely, not gradually. Check by comparison whether you have really arrived at the first tempo; after a slow middle section one easily stays below it. And read precisely whether tempo primo or a tempo stands: the two markings do not mean the same thing.