Paul Kurzweil

I've seen a lot of confusion about the definitions of half-time, double-time, and cut time in music theory, so here it is in a nutshell: Half-time doubles the tempo, because note values are cut in half, so a half note is played as a quarter note, which is half as long. This makes the tempo twice as fast. Double-time halves the tempo, because note values are doubled, so a quarter note is played as a half note, which is twice as long. This makes the tempo half as fast. It only seems like a contradiction if you mistake note values for tempo! Cut time is Alla breve, notated by a C with a vertical line through it after the time signature. It's just a change in the time signature, where the number of beats per measure (top number) and the division interval (bottom number) are both cut in half, so 4/4 becomes 2/2. It only affects the way notation is read, not played, therefore it does not affect tempo. It's useful sometimes for fast, simplistic charts, like for marching bands - it gives the musicians half the number of measures they need to read. In addition, these terms have nothing at all to do with the "feel" of a piece. A feel is subjective. Tempo is not. Tempo is an exact speed at which to play. When a drummer talks about "feel" they are not referring to tempo, they're referring to what the backbeat feels like to the listener. So when they talk about a half-time or double-time feel, they are not talking about tempo in the slightest. So, to recap: half-time is twice as fast, double-time is half as fast. Cut time is just for reading and has nothing to do with tempo, and neither does the "feel" of a beat. I hope this helps clear up the confusion!