Interval Identification
To calculate an interval requires visualizing it on your instrument. This exercise helps both interval identification on the staff, as well as interval identification on guitar and or keyboards. It also gives you a good foundation for reading music.
The mnemonic I've used here is:
Some kind of C to some kind D is some kind of second.
Some kind of C to some kind E is some kind of third.
Some kind of C to some kind F is some kind of fourth
Some kind of C to some kind G is some kind of fifth
Some kind of C to some kind A is some kind of sixth
Some kind of C to some kind B is some kind of seventh.
But it will also need to be drilled beginning on D, E, F, G, A, and B, yet not on every chromatic scale degree: Db and D# are "some kind of D", Eb and E# are "some kind of E", and so on.
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Video Lesson: