Understanding ground bass

Hi, I am Dr. Southall and I'm gonna be teaching you this music unit about harmonic progressions and basslines, so let's begin. In this lesson, we're going to be able to identify, understand, and compose a ground bass using bass clef. Let's begin. There's a number of different keywords for this lesson. We'll start with ground bass, which means a short, repeated bass line that repeats throughout a piece, forming the structure of the music. The second is baroque, a period in Western music between 1610 and 1750. The third is tonic, the first and most important note in a scale. It's often referred to as the home note. The fourth key term is dominant, the fifth note in the scale, which often feels like it needs to resolve the tonic. We'll talk a bit more about that in the lesson. And the last one is leading note, the seventh note in a scale, which often feels like it needs to resolve up to tonic. There's two parts to this lesson. The first is about ground bass. A ground bass is a repeated bass pattern which gives the music structure, and it's originally a concept from baroque music, which was music between the years 1600 to 1750. It's not uncommon to hear repeated bass lines in other styles of music as well. Pop music often uses chord sequences based on an idea very much like a ground bass. Listen to this very famous example of a ground bass. What instrument is playing the bass part? Make sure you download this file and listen to it outside of this video. Did you recognize the music? A ground bass in baroque music would often be played on a cello, and that was the instrument that you heard. It could also be played on a double bass, a harpsichord, or an organ, and these were all instruments of the baroque time, of course. Now, what musical features do you notice about this ground bass below? We have all the different notes composed onto the stave, but you can also listen to this track, which I recommend, on the audio file. So I'll play it through the video now, but you can obviously listen to this in your own time or rewind the video and listen to it multiple times if you need to. Here we go. (steady piano music) So what features do you notice about that? Well, Aisha says, "The pitch is low." Jun says, "The tempo is slow." And Sam says, "The pattern is repetitive," and, "The notes are equal length." Did you get any of those? I hope so. There are eight notes in the pattern. This is common if the ground bass is a four-bar phrase, each bar commonly uses two minims. Now, remember, a minim is a note that's worth two beats per bar. This particular pattern can be played in the F position. It's important we remember the correct technique to make performing as easy as possible. So we're not stumbling around with our fingers, we have them in the correct position so that those notes are easy to find and therefore easy to play. Let's do a quick check for understanding. A ground bass is, A, a repeated pattern of high notes; B, a pattern of notes played once only in a piece; C, a repeated bass pattern; or D, a pattern which develops slightly each time it is played. I think you know this, I think it's C, a repeated bass pattern. Now, this was a key term, so I'm just gonna say it all again. A ground bass is a repeated bass pattern. True or false? A ground bass can create a structure in a piece of music. Of course it's true. Well done. As it's repeated, one repetition can create a section within a piece of music. Which of the following is the correct F position? Is it this hand? Or is it B, this hand position? Or is it C, this hand position? Well done. The answer is B. Look at where those fingers are on each note, look at how they're spread out. That's the correct F position. Time for some independent practice. We're gonna practice this ground bass pattern. It starts with a C, G, F, G, F, G, A, B, which is the pattern we just heard a moment ago. You're gonna practice it as well, and I really want you to focus on where your hand is. So get that hand position exactly right, and the reason for that is it makes it much easier to play. I want you to identify the order of the notes. Play each note the same length. So we don't want any shortening of one of them and quickening up or anything like that, all the same sort of tempo. Play it at a slow tempo, so no rushing. And repeat the pattern, moving fluently from the end to the beginning again. So when you get to that A, B, you're gonna go right back to the C at the beginning. Good luck. I wish you well. I'm sure you'll do great. Hopefully you did really, really well. I suspect you'll agree with me that if you can get your hand in that correct position for F, it gets a lot easier, doesn't it? Okay, so what we're gonna do next is evaluate someone else's performance, because who doesn't like to be the teacher? We're gonna watch this video, and I want you to be critical of it. So think about how it could be even better. We're gonna offer constructive criticism. We're not just gonna say, oh, this wasn't very good, or that could have improved. Like, how could it have been better? Think of that key terminology that you could use to make your response really, really good. (steady piano music) (upbeat music music) There was some promising stuff in there, wasn't there, but what could be improved? Well, as a start, the hand position is correct. Hooray. The pitches in the ground bass are correct and in the right order. However, in the repeat, the rhythm was incorrect and it's not the same as the first time around. The third and fourth notes and then the seventh and eighth notes were played as quavers, which is not the right rhythm. As such, the rhythm does not match the time signature. However, the tempo stays consistent. The piece also ends on a C, rather than the B, as written. So there were some things that were done well and some things that were done correctly, but the things that didn't go so well, if you look at this model response, we've got really strong vocabulary to accurately tell us what the things were that could be improved, which is much better than just saying it could have been better or it could have improved in some ways, but not actually saying what those things are. All right, part two, composing a ground bass pattern. We love composing. Using the notes of a hand span in the F position, we're going to create our own ground bass. It should start on the tonic note and end on the dominant or the leading note. Do you remember what those things mean? Well, we're gonna have a look. So, first of all, we're gonna take a slight detour. Roman numerals are used to refer to each degree of the scale. So if you look at the scale, we've got C, D, E, F, G, A, B, C, and we have Roman numerals listed underneath each one, I, ii, iii, IV, V, vi, vii, and then I again, because we're repeating the note and going back into the kind of cycle. Now, the reason why we're gonna use Roman numerals for this is because there's a lot of numbers already used in music, such as in time signatures, beats, those sorts of things, and so it gets confusing if there's just numbers all over the place, 'cause they represent different things in different contexts. And so here we're using Roman numerals instead to differentiate what we're talking about. The tonic note is I and the dominant note is V. Remember that the tonic note is the first note in the scale and the dominant note is the fifth one. Now, the leading note is what we were talking about in the previous slide. That is the seventh note in a scale. Remember that from our key terminology? So just to recap, the tonic note is the first note in the scale and the leading note is the seventh note in the scale. Our ground bass will only use the notes F, G, A, B, and C. Remember, that hand position is gonna be really useful. Those notes transposed onto the bass clef look like these on the bottom here. Remember, that middle C is the one just above the stave. So for your composition, you're gonna start on the tonic note and end the sequence on either the dominant note or the leading note. It's your choice, okay? And the dominant note will be G and the leading note will be B. What impact does the tonic, dominant, and leading note have on the music? Well, Jacob says, "The tonic makes the music sound finished." Well done, Jacob. And Sofia says, "The dominant and leading note makes the music sound unfinished." Well done, Sofia. The tonic note helps reinforce the key of the music and is the final note of a piece. With a ground bass, the pattern continues throughout the music, so the last note of the pattern should feel like it wants to continue. The dominant creates tension to the stability of the tonic, making it sound unfinished and naturally returning back to the tonic. Now for a check for understanding. Which of the following notes would not be suitable to end a ground pattern: the tonic note, the dominant note, or the leading note? Well done, it's the tonic note. We've just mentioned this in the slide before. The tonic note makes it feel like it wants to go back into the leading note. Create an eight-note pattern played in minims. Remember, a minim is a two-beat per bar note. Keeping it short makes it more effective and memorable. So here we just have four bars and we're starting with the tonic, C, and finishing with the dominant, G. Your notes could be scalic, conjunct, or disjunct. Those are interesting terms, aren't they? We're gonna play you three examples, the first is scalic, the second is conjunct, and the third is disjunct, and then we'll discuss what each of these actually means once you've heard each clip. So let's start with scalic. (steady piano music) So that was scalic, and the reason we call it scalic is because it essentially moves in a scale pattern. So each note is sequential, so they follow the scale rather than jumping around in much larger steps. Let's try the second piece of music then. This is conjunct. (smooth piano music) So hopefully you can hear that that's not scalic because it's jumping a note in the scale each time. It's conjunct because that means it's moving no more than sort of a half or a full step at a time, so it feels quite smooth in its transition from one note to another. So by process of elimination, you can probably figure out what disjunct means, but let's have a listen. (tense piano music) So the key difference there is that between each note we're moving more than a step at a time. There's our labels, scalic for the first one, conjunct for the second one, and disjunct for the final one. If you want to go through those again, then please do rewind and listen to them so that you can hear those notes rather than just see them. And now we're gonna check how well you understood that. So which of these is a conjunct ground bass? Well done, the answer is A. A is a conjunct ground bass because it's moving no more than a step at a time between each note. All right, time for some independent practice. You're going to compose a ground-bass pattern on the keyboard and notate it using everybody's favorite clef, the bass clef. The success criteria is that you're gonna be using only the notes F, G, A, B, and C, like we have done in all of our examples. The pattern is eight notes played as minims. We're gonna start on the tonic note. End the sequence on the dominant or the leading note. I'll leave that choice up to you. And you're aiming for a mixture of notes that are conjunct and distinct. Aim for some technical accuracy as well, so make sure that your fingers are in the F position, and I want you to repeat the pattern a few times over. Best of luck. Remember, you can rewind to see examples if you're not sure of any of these terms. I think you're gonna do great. Okay, hopefully you did a really good job there. Similar to the last task, we're now gonna watch someone else doing this performance, and you're gonna be the teacher again. Bonus. And you're gonna decide what was great about it, but also how it could be even better. We're gonna be really constructive with our comments there and think carefully about using key vocabulary to describe accurately the areas for improvement. (steady piano music) Okay, so it might be that you've written some of the things that are similar to this model answer here, so I'm just gonna read it out. The composition uses notes just in the C position in the left hand, F, G, A, and C. There is some variation in intervals between the notes, a mixture of conjunct, disjunct, and scalic movement. There are eight notes in total and the ground bass starts on the tonic and ends on the dominant. The player is playing in the C position. The pitches were played accurately and the duration of each note was accurate at two beats in length. Okay, I hope you've enjoyed this lesson. We're just gonna do a quick summary as usual. Let's recap the main points. So, a ground bass is a short, repeated bass line that repeats throughout a piece, forming the structure of the music. Although originally used in baroque music, repeated chord sequences are still popular in today's music. A ground bass tends to start on the tonic note, which reinforces the key, and end on the dominant or leading note, both of which lead naturally back into the tonic. An effective ground bass can contain a mixture of scalic, conjunct, and disjunct notes, and we have composed a ground bass. Well done, everyone. I hope you've enjoyed yourselves and I'll see you next time.