Other rhythmic concepts

Hello and welcome to today's music lesson. I'm Miss Menzel and I'm gonna be your teacher for today. Let's get started. The outcome for today's lesson is I can identify key rhythmic features including anacrusis, polyrhythm, cross rhythms, and hemiolas. Let's look at some keywords for today. Downbeat, the first beat of a bar, which is usually emphasized. Anacrusis, a melody that begins before the downbeat. Polyrhythm, multiple different rhythms playing at the same time. Cross rhythm, a polyrhythm in which two or more of the rhythms conflict and feel like they have a different pulse. Hemiola, when three notes are played over the duration of two or vice versa, creating the feeling of tempo change. Today's lesson on other rhythmic concepts has three parts. Part one is the upbeat, downbeat, and anacrusis. Part two is polyrhythms, cross rhythms and hemiolas. And part three is diminution and augmentation. Let's get started with part one, the upbeat, downbeat and anacrusis. What is the rhythmic difference between these two melodies. Have a listen. (upbeat music) They both use the same note values, and if they were played without the drums, they would sound identical. Have a listen to that version. (upbeat music) The crucial difference is where they fit in relation to the bar. The first example you can have a listen to that, starts on beat one. (upbeat music) The second example, you can have a listen to that version, starts before beat one. You can see that highlighted there. (upbeat music) This makes them sound very different. Melody that starts before beat one uses anacrusis. You recognize this melody that uses an anacrusis. Have a listen. "Happy Birthday" Hope you recognize happy birthday. The word happy is on beat three with birthday on beat one. Beat one is called the downbeat because when a conductor shows the beats of a bar, beat one is in a downward motion. So you can see one, two, three, and four. And if you're doing three, you might do something like one, two, and three. You sometimes hear people talk about the upbeat because the final beat is going upwards. So you've got a down to start and an up to finish. An anacrusis is where the melody begins before the downbeat. As I was just showing you the last beat of the bar is always an upward motion. So this is called the upbeat. Which of these melodies features an anacrusis? Have a listen. (upbeat music) Which one did you think? It was the third melody. Let's do a check for understanding. Which beat is the downbeat? Is it A, one, B, two, C, three, or D, four? Which beat is the downbeat? Hope you all got that right. The downbeat is on beat one. An anacrusis is when the start of the melody comes when? Is it A, before the downbeat, B before the upbeat, C on the downbeat, or D on the upbeat? Which of those is it? It's A, an anacrusis is when the start of a melody comes before the downbeat. Let's do task A. Identify which beat of the bar each melody starts on and identify which melodies have an anacrusis. So identify which beat of the bar the melody starts on, and then say yes or no. Does it have an anacrusis? So pause the video and have a listen to the four clips. How did you get on with that listening exercise? Here are the answers. So for clip one, the melody starts on beat three. That is an anacrusis. For clip two, the melody starts on beat one, so that's not an anacrusis 'cause it's starting on the downbeat. For clip three starts doing beat two, so that is an anacrusis. And then for four, it starts on one, which is not an anacrusis. I hope you could hear all of that. Let's move on to part two of our lesson, polyrhythms, cross rhythms, and hemiolas. Many musical styles around the world are based on multiple layers of rhythms playing at the same time. Listen to this example of Gota music from West Africa. How many different rhythms are playing at the same time? Let's have a listen. How many rhythms did you think? You could have heard more than one rhythm. And you can hear up to three rhythms playing at the same time. So let's have a look at the word polyrhythm. So poly is a Greek word that means many. So polyrhythm means many rhythms. Polyrhythms must use rhythms that create a different feel to each other. If the rhythms sound like they're closely related, they're not a polyrhythm. This drum groove is based on repeated quavers and crotchets that fit neatly with each other and are closely related. It's not a polyrhythm. Have a listen. (funky music) Now have a listen to this groove, which uses rhythms that sound very different from each other and create different rhythmic emphasis. It's an example of a polyrhythm. Have a listen to that. (upbeat music) Let's check for understanding. Which of these clips does not feature polyrhythm? Have a listen to clips A, B, and C. (upbeat music) Which did you think? Well done if you've got B, that's the clip that doesn't feature a polyrhythm. A cross rhythm is a specific type of polyrhythm. A cross rhythm is where two or more different rhythms conflict with each other and create the feeling of having a different beat or pulse. To understand this we can listen to the rhythms separately first. How many beats are in the bar in these two simple rhythms? Have a listen to rhythm one. (gentle drum beat) And then rhythm two. (gentle drum beat) Rhythm one feels like three beats in a bar and rhythm two feels like four. When they're played together, the rhythms feel like they could be in either three or four, depending on how you hear it. Have a listen to that. (upbeat music) This makes it a cross rhythm because the two rhythms create a different feeling of the beat. We would call this a four three cross rhythm. One rhythm feels like it's in four and the other in three. Which two time signatures could we count this bit of music in? Have a listen. In this clip some instruments play that's counted in four, have a listen to those. (upbeat percussion) And some instruments play a rhythm that's counted in threes. So have a listen to that. (upbeat percussion) Together they create a four, three cross rhythm. Listen to that altogether. It's important to note that the players are not playing in different time signatures. In a cross rhythm it just feels like they are. The most common types of cross rhythms are four three and three two. One specific musical technique that creates a similar effect to a cross rhythm is the hemiola. A hemiola is when three equal notes are played over the duration of two beats or vice versa, the other way around. What effect does the hemiola have on the feeling of the beat halfway through this clip? Have a listen to the clip. (gentle music) What did you think? The hemiola gives the impression of a brief change of tempo. This is actually a rhythmic effect, not an actual tempo change. It's often used in music in three four. So have a listen to this. (gentle music) At the beginning, the pulse feels like groups of three beats. And then when you get to the hemiola, it emphasizes groups of two beats, which changes the feel of the music. It can also be used in compound time, like this example in six eight. Have a listen. (gentle music) So again, at the thought, it feels like three quavers in a beat, compound time, and then it feels like two quavers in a beat. So it feels like simple time. Can you identify which of these examples features a hemiola? You want to listen for the feeling of the pulse changing, even though it actually isn't. So have a listen to both of these examples. (upbeat music) Which do you think featured a hemiola? Well done if you've got the second one. Let's do a check for understanding. What's a cross rhythm? Is it A, more than one rhythm played at the same time? B, when two people play in different time signatures, or C, when two rhythms create different senses of beat? Which do you think it is? Well done if you've got C, it's when two rhythms create different senses of beat. What is a hemiola? Is it A, two notes played over the space of three beats. B, two notes played over the space of two beats. C, three notes played over the space of two beats. Or D, three notes played over the space of three beats. Which do you think? Well done if you got C. An example of a hemiola is three notes played over the space of two beats. So let's move on to task B. We want you to listen to each example and answer the questions. So for example one, how many different rhythms are playing simultaneously? What rhythmic feature is this an example of? What rhythmic feature is heard near the end? For example two, this feature's cross rhythm. What conflicting beats does it use? And describe the rhythms played on the drum. Pause the lesson. Have a listen to the examples and answer the questions. How did you get on? So for example one, you could hear five different rhythms playing simultaneously. And the rhythmic feature that's an example of is polyrhythm. Towards the end of the piece, you could hear a hemiola. For example two, the conflicting beats are three and four, and you could describe the rhythms played on the drum as repeated, syncopated and using fast notes, semiquavers. Let's move on to part three of our lesson. Diminution and augmentation. Augmentation and diminution are also rhythmic features. Augmentation proportionately lengthens the note values. Take this example, have a listen. (gentle percussion beat) Augmentation is where all the note values are doubled to create this in this example. Have a listen to what it sounds like when it's augmented. (gentle percussion beat) Diminution is where the note values are all shortened instead. So this is what it sounds like before diminution. (gentle percussion beat) And then this is what it sounds like when all the note values have been halved. (gentle percussion beat) Augmentation and diminution can use any proportion as long as all of the note values are changed by it. For example, this rhythm can be augmented by tripling the note values. For example, you can see this go from quavers to a crotchet to dotted crotchets and a dotted minim. Or you could use diminution on this rhythm by devoting the note values by four. Have a look at this. Why is it not an example of augmentation? Have a think. Well done if you spotted that only some of the note values have been changed by the same amount. Augmentation must change all of the note values. You can see there that the semiquavers have stayed the same between the two rhythms. So let's have a go at task C. We want you to augment this rhythm by a factor of two. So we want you to double the note values and then use diminution to shorten all of these notes by a factor of four. And then have a listen to this clip. Which rhythmic feature is used to change the initial rhythm? Why don't you pause the video and have a go at task C? How did you get on? So here you can see how this rhythm should be augmented. So you're doubling the note values. So your crotchets are becoming minims, your semiquavers becoming quavers, and your quavers becoming crotchets. And then when you're using diminution to shorten all of these notes by a factor of four, your minims are going to quavers. Your semi breathe is becoming a crotchet and your crotchets becoming semiquavers. And then the rhythmic feature that we use in the clip is diminution. Let's summarize today's lesson on other rhythmic concepts. Many melodies use an anacrusis to start before beat one. Remember, beat one is the downbeat. Polyrhythms include multiple rhythms that aren't closely related to playing together, creating a complex rhythmic texture. Cross rhythms create the feeling of different pulses playing simultaneously. Hemiola is used to create a brief effect of the pulse changing by playing three notes over two beats or vice versa. Diminution and augmentation develop rhythmic ideas by proportionally shortening or lengthening notes. I hope you've enjoyed today's lesson.