I am curious what you use scales for, so I made this poll. It was inspired by this question, which is a great question and if you have ever had the same question I think you will find my answer beneficial.
I got this question on youtube.
"OK, So I learn these. But I still don't understand how this help me play a song on the uke.
REPLY
View reply from TenThumbs Productions
Great question! Here comes the full answer.
Learning the C major scale won't help you to just play a song necessarily, but it would help you play a song in C, specifically it would help you to play the melody. When a song is "in the key of C" it determines two factors. 1. The chords that you can use and 2. The notes that you can used. That is because the chords are created from the scale. In the key of C you have C, Dm, Em, F, G, Am and B dim. All of these chords are created with the notes of the C major scale, that is why when you play the C major scale over those chords in sounds good.
So if you learn a song in the key of C, you can either use your ear or use sheet music to learn the melody, when you play the melody it will be in C, but knowing the notes of the key of C and these shapes it makes playing the melody sooooo much easier. So there is the first thing you can do, learn to play the melodies for the songs in the key of C. Now, if you learn how to transpose it, then you can learn to play the melody to any song, because you know all 5 shapes of all 12 major keys. Here is a video on transposition https://www.youtube.com/watch?v=6ehtXuK9dY8 Alright, so now we are playing the melody to any song in the major key, what else can we do with it? Two things, compose melody and improvise melody. You can use the major scale, and these shapes, to write songs, to be more exact, to write melody and once you have a strong melody you can write some lyrics. A lot of people write songs lyrics first, but it is because they don't know, or they are not confident with the major scale. The Beatles for example wrote their songs melody first. The melody for "Yesterday" came to Paul in a dream and to remember it he wrote down Scam-beld-eggs which he later changed to yes-ter-day, so by knowing these scales we can use them to compose melody, and a good melody is what makes a song memorable. Here is a video on how to write melody https://www.youtube.com/watch?v=88XDQLraRnc The scale would also be used to write riffs and licks for song as well, any melodic component to the song would be composed from the scale.
Lastly, improvisation. When a friend is playing a chord progression in the key of C you can use those scales to improvise a solo. By committing the shapes to memory you have mastered the technical aspect and the only limitation at that point is your creativity. Improvising melody and jamming with friends is extremely fun and rewarding and can provide hours and hours of entertainment.
Rock on friend!