Complete Guide to Time Signatures
The Basics of Time Signatures
A time signature is written as two stacked numbers:
- Bottom number: The note value representing one beat (always a power of 2). Here's what each number represents:
- 1: whole note (rarely used as a beat unit)
- 2: half note
- 4: quarter note
- 8: eighth note
- 16: sixteenth note
- Top number: How many beats per measure.
Examples:
- (also called Common Time): Four quarter-note beats per measure.
- (also called Waltz Time): Three quarter-note beats per measure (common in waltzes).
- (also called Cut Time or Alla Breve): Two half-note beats per measure, often used for fast passages.
- : Five eighth-note beats per measure.
Special symbols occasionally replace numbers:
- (Common Time) =
- (Cut Time) =
The time signature sets the foundation for the structure of the music.
Simple Time Signatures
Simple meters have top numbers 2, 3, or 4 (duple, triple, or quadruple meters). Each main beat divides evenly into two sub-beats (simple subdivision). This is the most common type of time signature in Western music.
Example:
- Counting: 1 & 2 & 3 & 4 &
- Metronome Setup: Set beats to 4, accent beat 1 (and optionally beat 3 for a secondary accent). Use quarter-note subdivisions.
Compound Time Signatures
Compound meters are characterized by the top numbers 6, 9, or 12 (which are multiples of 3). In compound time, each main beat is a dotted note (usually a dotted quarter note) and divides into three sub-beats. The main beats are felt on the first of every three sub-beats.
Example:
- Counting: 1 & a 2 & a
- Structure: Two main beats (each a dotted quarter note) per measure, each dividing into three eighth notes.
- Metronome Setup: Set beats to 2 (for the two main beats), use triplet subdivisions. Accent beat 1 (and optionally beat 2 for a secondary accent). Use quarter-note subdivisions.
Why multiples of 3? The top number tells us the total number of sub-beats (eighth notes in ). Since each main beat has three sub-beats, the total number of main beats is the top number divided by 3 (so has 2 main beats, has 3, has 4).
🔍 Note: The bottom number doesn't change counting. uses the same pattern as , but with sixteenth notes, making it twice as fast if the beat value is the same. In practice, the tempo (BPM) would adjust accordingly.
Irregular Time Signatures
Irregular meters (also called asymmetrical meters) have top numbers that are not multiples of 2 or 3 in the same way as simple or compound meters. Common examples include , , , and . They are frequently used in progressive rock, jazz, and non-Western traditional music. These meters create unique rhythmic feels and often shift the accent patterns in unexpected ways.
How beats are grouped:
Composers and performers often group the beats in irregular meters into smaller chunks (like 2+3 or 3+2 for ). This grouping is reflected in the beaming of the notes in sheet music.
- : Can be grouped as 3+2 (counted 1 2 3 1 2) or 2+3 (1 2 1 2 3).
- : Often grouped as 2+2+3 (1 2 1 2 1 2 3) or 3+2+2 (1 2 3 1 2 1 2).
📌 Key Insight: Beaming in sheet music reveals the grouping. Below are two examples of with different beaming patterns:
Metronome Setup:
- Set the total number of beats per measure (e.g., 5 for ).
- Accent the first beat of each group (e.g., in 3+2, accent beats 1 and 4).
- Use numbers only for the main beats (avoid "1 E & A") to avoid confusion. For sub-beats, you can use "&" for simple subdivisions or "& a" for compound-like subdivisions within the groups.
Practice Tips
- Identify the time signature in your sheet music.
- Analyze the grouping: For irregular meters, look at beaming or phrasing to determine the beat grouping.
- Set your metronome:
- Beats/measure → Top number (for irregular, set the total beats).
- Subdivisions → Match beat division (e.g., "&" for simple, "& a" for compound, or none for just the beats).
- Accents → Strong beat on 1, secondary accents per grouping (e.g., beat 4 in 3+2).
- Start slow! Gradually increase BPM as you gain confidence.
Frequently Asked Questions
Quick answers to common questions about time signatures.
Simple meters (like , ) have a march-like pulse (strong-weak or strong-weak-weak).
Compound meters (like , ) feel swaying or lilting (strong-weak-weak for each main beat).
No. Tempo (BPM) defines beat speed. Time signatures define beat organization. Adjust your metronome's beat count and accent pattern when the meter changes, but the BPM stays the same unless you change it.
Yes—they have the same beat count (4). The bottom number only changes the written note values, not the pulse. However, the choice might imply a different feel: might be used