Subtitles section Play video Print subtitles Hello, everyone. It's Zach here. And again, I've just been looking through the forums and looking for things people might need some extra assistance with, and might need some more kind of hands on examples. Of in order to understand it. So what one of these areas I think is key signatures. And just looking at key signatures determine what keys they represent, and how to go about actually working that out. So I'm just going to give kind of chatty informal. Example, flashing some on the screen and talking about how I would go through doing that. Now you can find this exercise at musictheory.net. I truly recommend it as a, a wonderful resource for you to go to and to use some of the practice exercises that they have. Certainly they'll be useful for getting to practice some of the things that we're talking about in this course. So let's have a, we look at some key signatures. There's a few ways of going about this and I'm sure there's people on the forums and people taking the course certainly have different ways of doing it. I'm just going to show you a few different ways that you could do it. But certainly if anyone else has got any useful tips out there, please feel free to share them with the rest of the group. Now, I'm looking at this, and I'm seeing that there's an F sharp, C sharp, G sharp, and D sharp. What I would say is eventually you'll get used to that. You'll be able to look at this immediately and see which key it is, just by the shape. Just by seeing the, the, the, the fact that there's four sharps there. But let's work it out. So, this is a little trick that you can use for sharp keys. If you look at the very last sharp in any key signature, and raise it by a semitone. That gives you your answer. That is the key. So, in this case we've got D sharp as our last sharp. Raise D-sharp by a semitone, so it gives us E [SOUND]. Click on E. We get the answer right. Okay, now we've got another sharp key here, so C-sharp is our last sharp. So if we raise up by a semitone it gives us D. Now, I'm not going to click it right away because I just want to explain that to you. Another way of thinking about this is that the last sharp in the key signature is the leading note of the key. Okay. So C sharp is the seventh degree of the scale, of D major. That gives us our answer, D major. So of course we're just dealing with major keys here. Each one of these also relates to its relative minor. So we just said that the last one was D major. It's relative minor would be. B minor, and that would also be a perfectly acceptable answer for the question, which key does any given key signature represent. It would be either the major or the relative minor. But just for the ease of explanation in this little video, I'm just going to stick to majors because I think people would probably prefer that at this stage. We can go into it in more depth later on or in the forums. So again, I've got sharp keys, and I'm going to look at the last sharp here. The last sharp is G sharp. Now, a semitone above that is A. We know that this is the key signature for A major. It could also be the key signature for it's relative minor, which is F sharp minor. But at this stage I'll just say we're just dealing with major keys. So that's looking at the last semitone. Counting them up. sorry, looking at the last sharp, counting up one semitone, and getting our answer. Obviously, another way we can do this is to be a bit more kind of thorough. Go back to the, the first transpose, and we could use the circle of fifths. So what we can see is this one sharp, two sharps, three sharps. So that is three steps clockwise round the circle of fifths from the key of C, which has no sharps or flats. So if we imagine C being at 12 o'clock on the circle of fifths, and we go one step clockwise, well, we get C, D, E, F, G. That takes us to G. That would be our first stop. G, A, B, C,D, D will be our second stop. D, E, F, G, A will be our third stop and there is no stop at number three is because we've got three sharps in the key signature, and again that gives us the answer A. So you can choose one of these options. You can either count how many sharps there are and go around that number of sharps in the circle of fifths. Or you can look at the last sharp and raise it by a semitone. Or indeed, as we've just done here, you can do both, and use them as checks against one another. So in this case, we're going to select A. Okay, and this next one, we can do both options. Let's run through this a bit quicker, now. If we look at the last sharp, we've got A sharp. Raise A sharp by a semitone, we get B. Very simple, very easy. If we wanted to do it using the circle of fifths, what we could do is it's one, two, three, four, fifth. Five. Five sharps. So we would carry the five. Positions. Round the circle of fifths from C at the top, at the 12 o'clock position. So, if we do that, we get C to G is one. G to D is two. D to A is three. A to E is four. A, E to B is five. So again, both methods take us to the same answer and that is B major. Okay, so here's a flat key. Now this has just got one flat. Well if we go, if we use a similar example, we can say we're going to go one step round the circle of fourths because we're dealing with flats here, so we're going anticlockwise. And if you go one step anticlockwise. Round the circle. We can see that this is a movement of a fourth, and this takes us to F. C, D, E, F. One, two, three, four. Now, the key signature that just has a B flat is F major. Again, of course it could be D minor, it's relative, but at this stage we're just going to consider this as F major. So we've just got one flat. We're going to move one step. Round the circle, anti-clockwise, to get from C to F. F is our answer in this case. Okay, we're back to a sharp key again, and what we see is that the last sharp, because it is only one, is F sharp. A semitone above that is G. Let's use our circle of fifths method. Got one sharp so we'll go one position around from C. C to G is one position on the circle of fifths, G major. Now, this one, because it doesn't have any sharps or flats, obviously we know that to be C major. Let's skip through this a bit quicker now. We've got two sharps. Last sharp is C sharp, so it mean's we're going to be in D. No sharps or flats, C. Four sharps, you look at the last one. You've got D sharp. Up a semitone, that gives us E. No sharps, C. Now this is being presented to me in a random order. That's why we're getting some repetitions here. Three sharps, look at the last one. Last one's G sharp. Up a semitone from G sharp gives us A. Like this. Okay, so apology's that the screen has all of the sudden changed, but what I wanted to do is show you just a little bit more of the screen, and draw your attention to this area that the cursor's on at the moment. And what this does is it allows you to customize the exercise. So what I'm going to say is we're going to stick to just the general clef for just now, and we're going to have. All of our key signatures, I'm going to click on all of these options here. You maybe can't see some of what I'm doing, but all I'm doing is showing you that you can use this menu to customize the exercise. So I've just made that we bit harder, and what I'm going to do is get rid of that and start the next exercise. So, when we're using flat keys, there's another little trick that we can use. [COUGH] And that is really simple, that the second last flat is the keynote. We don't need to do anything to it, we don't need to raise it by a semitone or lower it by a semitone or anything like that. We just look at the second last flat, and that is the keynote. Now this is only slightly problematic if you think about the key that has one flat in it, because they can't have a second last flat because it's only got one flat. If we just remember that that's F, or remember that we can one-step around the circle anticlockwise because we're dealing with flats. We can get to the answer F. But if we just remember that we can use this little trick for the rest of the key signatures. So if we look at the second last flat here, we've got a D flat. That's our answer. D flat major is the key signature. Of course that can also be B flat minor, is relative minor. But again we're just dealing with major keys in this example. Okay, we're going to look at the last sharp here, and this is a really interesting one that I want to show you. You've got an E sharp. Now E-sharp, what is a semitone above E sharp. Well, it's not F, as some people might be thinking, because remember, E and F are already a semitone apart. So, a semitone above E sharp is actually F sharp. B flat and E flat. We look at the second last flat, and we can see that that's B flat major. I just want to prove this to you again by walking through the circle of fifths example. no, we're dealing with going ant-clockwise, because we've got flats here. So if we move one step around we've gone from C to. F. That's the movement of a fourth, because we're going anti-clockwise. If we go another fourth around we get from F to B flat, and again, as we said, by looking at the second last flat, B flat major. Okay, so this is just one sharp. If we look it, at the last sharp in a key signature and go a semitone up from it. This is F-sharp, a semitone up gets us to G-major. So there's your answer. This one, as I said, we can just either remember that one flat is F-major. Or we can look at the circle fourths, which is anticlockwise around the circle of fifths, and we can say. Okay, it's got one flat, so we're going to move one position around. One position around from C, with no sharps or flats, takes us to F with one flat. So it's F major. Again, we look at the second last flat here, and we see that this is the key of E flat major. If we were to work around the circle of fifths example, we would go from C to F. We have an anti-clockwise, so we're moving in terms of fourth. We'd go from C to F, which is one flat, F to B flat, which is two flats, B flat to E flat, which is three flats. So again, we've got E flat major here. Again, one flat on this one, is F Major. So we've done quite a lot of examples and that's why we're starting to get repetitions here. So I'm going to leave that there and hopefully that will be of use to people. Please feel free to comment or get in touch and let us know if you would like any more examples of this. But hopefully this has been useful for you in the meantime.
A2 sharp flat semitone major circle signature Lecture 2 Extra 1 - Key Signature Demonstration (Coursera - Fundamentals of Music Theory 13) 30 5 songwen8778 posted on 2016/07/28 More Share Save Report Video vocabulary