Doppio movimento

The player reads “Doppio movimento” in the notation and adjusts to a tempo twice as fast. The marking acts on the tempo, not on the note values: the quarter note, which looks the same in the notation before and after, afterwards lasts half as long. The metronome would have to be set to double the number.

How to apply it

The two lines above have the same notes and differ only in tempo. That is exactly how you read the instruction: you take over the rhythm unchanged and speed up the pulse. If you use a metronome, you double the number: quarter note = 60 becomes quarter note = 120.

Doppio movimento or l'istesso tempo?

Both markings appear at a change but mean opposite things. L'istesso tempo says that the beat stays the same despite a new time signature or new note values. Doppio movimento demands a real acceleration by a factor of two. You return to the previous tempo with a tempo or tempo primo.

Alternative ways of writing

Instead of the words there is sometimes a new metronome mark, or the note values are halved at the same time. Then the music looks different but sounds twice as fast as before.