When a piece of music builds toward an emotional peak, the beat doesn't just get louder—it races forward. The primary musical term for speeding up tempo is accelerando, usually abbreviated as accel. in sheet music. This Italian directive instructs performers to gradually increase their speed, transforming a static rhythmic pulse into a surging wave of momentum.
Understanding how to execute and interpret this dynamic shift is essential for any instrumentalist, vocalist, or conductor. While casual listeners notice the rising energy, musicians must navigate the technical hurdles of keeping a speeding tempo tight, controlled, and musically expressive.
Defining Accelerando and Related Terms
To master tempo changes, you first need to separate accelerando from other tempo-modulating directions. Misidentifying these terms can ruin the intended phrasing of a composition.
- Accelerando (accel.): A gradual, continuous increase in speed over a specific duration.
- Stringendo: Literally meaning "tightening," this term often implies speeding up, but it typically carries a heavier emotional urgency or pressure than a standard accelerando.
- Ritardando (rit.) or Rallentando: The direct opposite, instructing the ensemble or soloist to gradually slow down.
- A Tempo: A directive telling performers to return immediately to the original base tempo after an alteration.
Unlike sudden tempo jumps, an accelerando creates a bridge between two distinct speeds. It requires careful pacing so the music doesn't lurch forward awkwardly or speed up too early in the phrase.
How Composers Notate Rhythmic Acceleration
Composers use various notation methods to communicate how fast a tempo should increase. In traditional Western staff notation, the term accelerando appears below the staff, often accompanied by dotted lines or abbreviations.
When looking at a score, you will encounter different structural approaches to speeding up:
- Gradual Drift: The word accel. stretches across several measures, leaving the exact rate of increase up to the performer's interpretation and the conductor's baton.
- Piu mosso: Meaning "more motion," this indicates an immediate step up to a faster tempo rather than a gradual slide.
- Metric Modulation: A more mathematically precise technique where a specific note value in the old tempo is equated to a different note value in the new tempo, creating an exact proportional shift in speed.
You can explore detailed notation standards through resources like Dolmetsch Online Music Dictionary for a deeper look at historical score markings.
Technical Execution for Performers
Speeding up without losing control is one of the hardest challenges in ensemble playing. When adrenaline kicks in, musicians tend to rush prematurely. Executing a clean acceleration requires specific physical adjustments.
Subdividing the Beat Internally
As the overall tempo increases, your internal subdivision must become sharper. If you're playing eighth notes at 80 beats per minute and accelerating toward 120 bpm, your brain has to track the underlying pulse with absolute precision. Losing that internal grid leads to dragging or rushing among section members.
Balancing Dynamic Growth
An accelerando rarely happens in isolation. Composers almost always pair an increase in speed with a crescendo—getting louder as the music speeds up. The two elements feed off each other. If you speed up without adding sound density or volume, the passage loses its dramatic punch.
Managing Physical Tension
Fingers, bow arms, and vocal cords tense up naturally when playing faster. Consciously relaxing your wrists and breathing with the phrasing prevents your technique from locking up mid-acceleration. For deeper technical exercises on rhythmic control, check out the Juilliard School Open Music Theory resources.
Common Mistakes to Avoid
Even advanced musicians fall into predictable traps when executing speed changes. Recognizing these pitfalls helps keep your performances clean.
- The Cliff Effect: Speeding up too fast in the first two bars of an eight-bar accelerando, leaving nowhere left to grow by the climax.
- Ignoring the Accompaniment: If only the lead melody speeds up while the rhythm section stays put, the ensemble falls apart. Every voice must scale the tempo together.
- Rhythmic Unevenness: Surging forward on easy notes and dragging on technical passages. The acceleration curve must remain smooth and linear.
Frequently Asked Questions
What is the abbreviation for accelerando in sheet music?
It is most commonly abbreviated as accel. You may also see loco or descriptive phrases like poco a poco accelerando (speeding up little by little).
Is accelerando the same thing as rubato?
No. Accelerando is a deliberate, directional increase in tempo. Tempo rubato involves flexible, elastic timing where beats are subtly borrowed and paid back within a measure, without necessarily raising the overall speed of the piece.
How does a conductor signal an accelerando?
A conductor will typically expand their rebound gestures, making the beats slightly closer together in time while using broader, more energetic motion to signal the rising tension to the orchestra.
Can an accelerando happen instantly?
No. By definition, accelerando means gradually accelerating. An instant change to a faster speed is marked as a sudden tempo shift or piu mosso.
