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Lesson 6: Constant versus changing time, adding triplets, and duplets

Created by All Star Orchestra.

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  • piceratops tree style avatar for user Free Spirit
    What is a movement?
    (34 votes)
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    • piceratops ultimate style avatar for user Rachel
      A movement is a section of the song. It's like a song in and of itself but connected to the other movements to create the whole idea of it. Like, if you had a song about winter you might have a movement about holidays and another about snow.
      (40 votes)
  • blobby green style avatar for user Creativ Genius
    At would it be possible if the actual notes were played to reveal the measure/beat/timing/tempo?
    (7 votes)
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  • blobby green style avatar for user Nancy Otta
    Would the theme from Jaws be an example of changing time?
    (3 votes)
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  • winston baby style avatar for user Olivia M-fo-mushroom
    I'm still slightly confused about one thing. Are duplets like triplets, but with quarter notes instead of eighth notes?
    (1 vote)
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    • old spice man green style avatar for user Josh (SpongeJr)
      No, it's different... we're talking about putting a "two-feel" over top of what is normally a "three-feel". For simplicity, let's think of a waltz, going ONE two three, ONE two three, ONE two three...

      Do "ONE two three..." for a while like that and start tapping your foot or clapping or whatever on the ONEs. Now comes the tricky part. Tap or clap again right in-between the "two" and "three" without changing the tempo or anything. If "one-two-three" were quarter notes in 3/4 time, you are going to clap or tap on the "upbeat" or "and" of two. ONE two AND three, ONE two AND three.

      When you get the feel for this, this is the general idea of a duplet, and what I mean by it being a "two feel" over top of a "three feel".

      You can have much more complicated things, like 7 notes over the time of 3 beats, which is quite strange for the brain to do accurately, and more complicated things yet, but they are rare or absent in many music forms.
      (10 votes)
  • aqualine ultimate style avatar for user Jenna  Williamson
    I've heard about the musical harmonic series before, but I don't really know what it is. Does anyone know how to explain it? I'm trying to be a composer.
    (2 votes)
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    • leafers sapling style avatar for user Lemur2
      A musical harmonic is, for example on a violin your finger doesn't push down on the string, but instead barely touches it when your up really high...so the harmonic is lets say for example, A, you would shift your fingers up and barely touching the string you make the same exact sound but up higher...hope this helped....if not clear please tell me...
      (3 votes)
  • hopper jumping style avatar for user Sorgan71
    I play music and I dont know what the SFP and then a crecendo to F is and i see it in by part for a cristmas festival. Could you help me?
    (3 votes)
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  • duskpin ultimate style avatar for user 8ooks
    why would people want to change meters in music?
    (2 votes)
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  • marcimus pink style avatar for user petra.dlamini789
    why are they called half notes,8th notes and so on?
    (2 votes)
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    • leaf blue style avatar for user Peterson
      This is because they are rhythmically considered in fractional relationships to a whole note (which we say has four beats). Thus, a half note is two beats in duration, and an eighth note is one-eighth of a whole note (eight notes fit into one whole). This relationship is true for all other notes.
      (2 votes)
  • duskpin ultimate style avatar for user CHR!$
    Does anyone know what an excerpt is?
    (1 vote)
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  • hopper happy style avatar for user Ami
    What are sonatas, sonatinas, allegros, and movements?
    (2 votes)
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    • piceratops ultimate style avatar for user JJ Sutton
      Sonatas and sonatinas are forms of music. Like a 5-paragraph essay, or a novel, they have certain parameters that must be met for them to be an official sonata or sonatina. Allegro is a tempo marking, which roughly means fast. Allegro is often used as the title for a fast movement. A movement is a part of a musical work, such as a symphony or sonata. Slight pauses between each movement show their separation.
      (2 votes)

Video transcript

- [Voiceover] At times, especially in popular dance forms the meter will remain constant. All ballroom dancing fits into this category. A march would also fit into this category, remaining constant, usually in two-four. It is also the case with most music from the 18th and 19th centuries. In the latter part of the 1800's and into the 1900's, composers started to feel free to change meters during a movement or work, sometimes quite often. The actual meters remain as we have discussed. If we look at the last movement of the Sam Jones "Cello Concerto", we can see some simple changes of meter, from two-four to three-four, back to two-four, then three-four and four-four. ("Cello Concerto" by Sam Jones) Another simple example is in Phillip Glass' "Harmonium Mountain". At this excerpt, he mixes the meters two-four, three-four, and four-four. ("Harmonium Mountain" by Phillip Glass) If we look at David Stock's work called "Blast" written in 2010, we find a more complicated section of meter changers, using five-eight, seven-eight, three-four, and four-four. ("Blast" by David Stock) If we look at a four-four measure, we have learned that the measure can easily be divided by using various note lengths. Half notes, quarter notes, sixteenth notes, thirty-second notes and so forth. But what if a composer would like to divide one of those quarter notes into three equal parts to create more rhythmic interest? We accomplish this by adding a three above or below a group of three eighth notes. The three signifies that three notes are performed during the time of one quarter note. Let's again look at Phillip Glass' "Harmonium Mountain". In this passage we see the violins playing the groups of three called triplets, and the violas and cellos are playing quarter notes. Then the violas join the violins playing triplets, the cellos play the eighth notes and the double basses play the quarter notes. ("Harmonium Mountain" by Phillip Glass) This method of changing duple notes to triple notes can work in any duple meter. The composer can also divide the triple beat in different ways. For example, instead of three eighth notes in a beat, we could see an eighth note and a quarter note, or a quarter note and an eighth note. We still need the number three above or below the notes. If we look at Ravel's "Daphnis et Chloe" the meter is five-four, but Ravel adds the three for each part to create triplets. You will see that he doesn't continue to write the three during the continuation of the excerpt, assuming that the performer understands the pattern. ("Daphnis et Chloe" by Ravel) The triplet is the most common variation within a meter, but there could also be, for example, five notes within a quarter, again with a five above or below, or six, or quite frankly any number that is not common to the meter. In a triple meter like six-eight, one could do the same. Six-eight can be one dotted half note or two dotted quarter notes, or six eighths, or twelve sixteenths. We could also have a rhythm of quarter, eighth, or eighth, quarter. Or any combination that adds up to six eighth notes. If a composer wanted four notes during a dotted quarter note, the number four would go above or below the group of notes. As you can see, the notation of rhythm can become very complicated. We will discuss this in later lessons.