Time signatures are an important component of any piece of music, as they indicate the musical beats of the song. Although they may seem deceptively simple, they can get complicated when you try to calculate them based on the music you watch or listen to. Before you get into it, make sure you know the basics of what constitutes a time signature, so that it is easier for you to see or hear it when you need it.
Method 1 of 3: Learn the Basics of Time Signatures
Step 1. Distinguish between simple and compound time signatures
Find the time signature at the beginning of the song, just after the treble clef or bass clef. A simple time signature means that a regular note (not a dotted one) receives the musical hit, such as a quarter note, a half note, or a round note. In a compound time signature, the dotted notes receive the musical beat, such as a dotted quarter note, a dotted white note, and so on. The main way to identify a compound measure is to look at the top number. If it is a compound measure, the top number must be 6 or higher and also a multiple of 3.
- Following the rule of compound bars, 6/4 is a compound measure because there is a "6" at the top, which is a multiple of 3. However, 3/8 is a simple measure because the top number is less than 6.
- Time signatures are also called meter signatures, and time signatures tell you the metric of the song.
- Looking at the top number, it tells you the time signature of the song: 2 = simple double, 3 = simple triple, 4 = simple quadruple, 6 = compound double, 8 = compound triple, and 12 = compound quadruple.
Step 2. Identify which note gets the musical beat in a single time signature by looking at the bottom number
The bottom number in a simple time signature tells you which note gets the musical hit. For example, "4" indicates that the black one gets the musical hit, while "2" indicates that a white one gets the musical hit.
- The lower numbers in a simple time signature always refer to a specific note that receives a single musical beat:
- A "1" at the bottom indicates that the round receives the musical hit.
- "2" means that the white is equal to 1 musical beat.
- "4" tells you that the black gets the musical hit.
- When you see an "8", it means that the eighth note lasts for a musical beat.
- Finally, a "16" tells you that the sixteenth note gets the musical beat.
- For example, a 4/4 time signature is a simple time signature. The "4" at the bottom tells you that the quarter note is getting the musical hit.
Step 3. Calculate which dotted note receives the musical hit in the compound time signatures
In the case of compound bars, this is a bit more complicated, since you could describe it in two ways. A dotted note always takes the musical hit, but you can also see it as a division of a dotted note, divided into 3 shorter notes of equal length.
- For example, each of these lower numbers tells you the following in a compound bar:
- A "4" means that the dotted white receives the musical hit, which can be divided into 3 quarter notes.
- An "8" tells you that the dotted quarter note receives the musical hit, which is equal to 3 eighth notes.
- A "16" tells you that the dotted eighth note receives the musical hit, which is equal to 3 sixteenth notes.
- The 6/8 time is a compound time signature. The "8" indicates that a dotted quarter note receives the musical hit, however, it can also be said that a simple musical hit is composed of 3 eighth notes (the same length as a dotted quarter note).
Step 4. Calculate how many musical beats are in one measure
The top number tells you how many musical beats each measure has. For single bars, just read the number to get the number of beats per measure. For compound bars, divide the number by 3 to get the number of beats per measure.
- For example, 2/4 has 2 musical beats per measure, and 3/4 has 3 musical beats per measure. They are both simple bars.
- In the case of compound bars, 6/8 has 2 musical beats per measure, while 9/12 has 3 musical beats per measure.
Step 5. Learn the basic values of the notes
When talking about note values, a 4/4 time signature is generally assumed because it is the most common time signature. In that case, the quarter note is the note is filled with a stem, and receives 1 musical hit. The white ones are equivalent to 2 musical hits and are hollow with a stem, while the round ones consist only of a hollow circle equal to 4 musical hits. The eighth notes are equivalent to a musical half beat, and have a solid circle with a flag in the upper right part of the stem, although they are sometimes connected to each other at the top.
Rests also take musical hits, just like their note equivalents. A quarter rest looks almost like a stylized 3, while a white rest is a small rectangle at the top of the midline. A round rest is a small rectangle below the second line from the top, and an eighth rest is a stem with a small left flag at the top
Method 2 of 3: Decipher a time signature by taking a look at the music
Step 1. Decipher the number of musical beats in the measure
When looking at a piece of music, you will see 5 lines running parallel to each other across the sheet. On those lines, you will see vertical lines that divide the music into bars. A compass is the space between two vertical lines. To find the beats in a measure, count the notes using a quarter note as the basic beat.
- Write the number of musical beats that each note has above the beat, then add them all together to determine the beat.
- For example, if you have a quarter note, a half note, and a quarter silence, then you have 4 musical beats since the quarter note is equivalent to a musical beat, the white one is two strokes, and the quarter note is equal to a musical beat.
- If you have 4 eighth notes, 2 quarter notes, and one round note, you have 8 musical beats. The 4 eighth notes are equal to 2 beats, while the 2 black notes are equal to 2 beats and the round one is equal to 4 beats.
- If you have 2 quarter notes and 2 eighth notes, then you have 5 musical beats, since each quarter note equals 2 beats and the 2 eighth notes equal 1 beat.
Step 2. Look at the length of the notes to decide which time signature fits best
For example, if most of the notes are black and white, it might make sense for the quarter note to be the musical beat. If there are more eighth notes, it may make sense for the eighth note to be the musical beat. Basically, you need to make it as easy as possible when you go to count the tempo, and therefore the notes that appear the most should take on the musical beat.
- For example, if the notes are 2 quarter notes, a quarter note, and a quarter note rest, the time signature could be 6/4 or 12/8. If it is 6/4, the black one would receive the musical blow. In the case of 12/8, it would be the dotted white, but normally more eighth notes are seen in that time signature since 1 musical beat equals 3 eighth notes. In this case, 6/4 probably makes more sense.
- If the notes are 2 white and 2 black, they could be 2, 5/2, 5/4, or 10/8. You shouldn't use decimals, so 2, 5/2 is out. A 10/8 time signature doesn't make much sense since there are no eighth notes, so 5/4 is the most likely signature, in which you will count the quarter notes as a musical beat.
Step 3. Aim for the longest possible note value when counting the musical beats
In general, when deciding on a time signature, try to count the value of the longest note as the base beat, which means determining which note gets the beat. For example, count the whites as the musical hit if you can, but if that doesn't make sense, move on to counting the quarter notes as the musical hit.
In the example of 2 white and 2 black, 2, 5/2 would count the white as the musical hit, but since decimals are not allowed, choose the next longest musical hit, which would be the quarter note
Step 4. Examine how the eighth notes are grouped to help decide between "4" and "8"
When the bottom number of the signature is 4, the eighth notes are often grouped into groups of 2, connected at the top with their flags. On the other hand, if the eighth notes are in groups of 3, that means that the bottom number of the time signature is 8.
Method 3 of 3: Listen to a time signature
Step 1. Begin by looking for the main pulse or rhythm
When you go to listen to a song, you can start tapping or nodding to the beat. This rhythm is known as the pulse, which is what you must count when playing the song. Start by looking for this rhythm and tapping along with it.
Step 2. Determine if you can hear an emphasis on certain beats of the percussion
Even beats are often given an additional beat or sound, particularly in rock or pop music. For example, you may hear "bang, bang, bang, bang" as the rhythm, but you can also hear a little more in some rhythms, such as "bang, bang, bang, bang."
Many times, the first musical beat of the measure is given a stronger emphasis, so try to listen to that as well
Step 3. Listen to the background beats for an emphasis from other instruments
Although the drums usually play on the even beats, other instruments in the song may play the backbeats or the odd beats. So while you can hear a more solid sound on even hits, listen to the other musical hits for emphasis elsewhere.
Step 4. Check for major changes in the first beat of the measure
For example, you may hear chord changes on the first beat of most bars. Alternatively, you can hear other changes, such as melody movement or harmony changes. Often times, the first note of the measure is where the biggest changes in the song occur.
It can be helpful to hear the strong and weak notes. For example, the hits for the double time (2/4 and 6/8), are strong-weak. The hits for the triple (3/4 and 9/8), are strong-weak-weak, while for the quadruple (4/4 or 'C' for the common time and 12/8), they are strong-weak- medium-weak
Step 5. Try to listen to how the punches are grouped based on the signals
For example, you may notice that the hits are grouped into 2, 3, or 4. Count the hits if you can. Listen to the first beat of each measure, then count the notes, 1-2-3-4, 1-2-3, etc., until you hear the first beat of the next measure.
Step 6. Choose the most likely time signature for the song
If you hear 4 strong beats in one measure, you probably have a 4/4 time since it is the most common in pop, rock and other popular music. Remember, the "4" at the bottom tells you that the quarter note is the musical beat, and the "4" at the top tells you that you have 4 beats in each measure. If you feel 2 beats, but also hear notes in triples behind it, it may be a 6/8 measure, which is counted in groups of 2 but each of those beats can be divided into 3 eighth notes.
- A 2/4 time signature is most often used in polka and marches. You can hear "om-pa-pa, om-pa-pa" in this type of song, where the "om" is a quarter note on the first hit and the "pa-pa" is 2 eighth notes on the second hit.
- Another possibility is 3/4, which is often used in waltzes and minuets. Here, you hear 3 beats in the bar, but you will not hear triplets that are made in a 6/8 bar (a triplet is 3 eighth notes).
- At the slower tempos, all eighth notes are counted in measures of 12/8, 9/8, 6/8, and 3/8.
- If you see "C" in the time signature, it means "common time" or 4/4. A "C" with a line through it means "time cutoff," which is 2/2.