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

Created by All Star Orchestra.

## Want to join the conversation?

• What is a movement?
• 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.
• Would the theme from Jaws be an example of changing time?
• I think that that would be more of an accelerando (just getting faster and faster) rather than actually changing the time signature (how many beats per measure).
• At would it be possible if the actual notes were played to reveal the measure/beat/timing/tempo?
• A movement is when divide diffrent notes into a three beat or 4
(1 vote)
• I'm still slightly confused about one thing. Are duplets like triplets, but with quarter notes instead of eighth notes?
(1 vote)
• 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.
• Are duplets just a set of two notes that take up one beat? Triplets are three, so are Duplets two?
• No, actually it's two notes that take up three beats, for example an eighth note duplet would actually take up the time of 3 eighth notes
• How can you performs 3 eight notes in the same time as a quarter? Since quarter is a measure of time, and eighth is a measure of time? That's like saying you can squeeze 3 eights of a second inside one fourth of a second. Makes no sense.
• Triplets aren't made up of eighth notes, just notated similarly to them. Mathematically speaking, a triplet that takes up the space of a quarter note is a set of three twelfth-notes, but we don't refer to them that way in music.
• Could you put 15 on top of the notes?
• Seeing that the time signature can change is only confusing me all the more as to why we need to designate them in the first place... :(
• Time signatures are there to give the music a ''feel''. A waltz is only a waltz if it's in 3/4 (or other triple time). A piece in 3/4 feels different from one in 6/8, even though they have the same number of quaver beats, because the emphasis is in different places. A composer will change time signature to give a music a different mood, but if he didn't use a time signature he would have to write the new emphasises out by hand. So basically time signatures are shorthand for putting in emphases on notes in a regular pattern.