Sunday, May 8, 2011

More theory by demand


     An interval is the distance between two notes. Intervals are always counted from the lower note to the higher one, with the lower note being counted as one. Intervals come in different qualities and size. If the notes are sounded successively, it is a melodic interval. If sounded simultaneously, then it is a harmonic interval.      The smallest interval used in Western music is the half step. A visual representation of a half step would be the distance between a consecutive white and black note on the piano. There are two exceptions to this rule, as two natural half steps occur between the notes E and F, and B and C.
     A whole step is the distance between two consecutive white or black keys. It is made up of two half steps.


Qualities and Size
Intervals can be described as Major (M), Minor (m), Perfect (P), Augmented (A), and Diminished (d).
Intervals come in various sizes: Unisons, Seconds, Thirds, Fourths, Fifths, Sixths, and Sevenths.

2nds, 3rds, 6ths, and 7ths can be found as Major and Minor.
Unisons, 4ths, 5ths, and Octaves are Perfect.

When a major interval is raised by a half step, it becomes augmented.
When a major interval is lowered by a half step, it becomes minor.
When a major interval is lowered by two half steps, it becomes diminished.
When a minor interval is raised by a half step, it becomes major.
When a minor interval is raised by two half steps, it becomes augmented.
When a minor interval is lowered by a half step, it becomes diminished.
When a perfect interval is raised by a half step, it becomes augmented.
When a perfect interval is lowered by a half step, it becomes diminished.

     Intervals can be inverted, which basically means you turn them upside down. The lower note is raised up an octave so that the top note/bottom note relationship is reversed. The chart below shows the inversions of intervals.
  • Major becomes Minor
  • Minor becomes Major
  • Perfect remains Perfect
  • Augmented becomes Diminished
  • Diminished becomes Augmented
  • 2 becomes 7
  • 3 becomes 6
  • 4 becomes 5
  • 5 becomes 4
  • 6 becomes 3
  • 7 becomes 2

Interval Identification
     It is important to be able to hear and identify intervals. This is a very important thing for musicians to do. Here is a list of familiar songs that will help you to identify the intervals.

m2- Stormy Weather m2
M2- Happy Birthday M2
m3- The Impossible Dream m3
So Long, Farewell from The Sound of Music
M3- Halls of Montezuma M3
P4- Here comes the bride P4
A4- Maria from West Side Story A4
P5- Star Wars P5
Twinkle, Twinkle, Little Star

M6- NBC theme music M6
m7- Somewhere from West Side Story m7
M7- Bali Hai from South Pacific
Octave- Over the rainbow Oct.


  1. This is actually really great stuff. If I was taking music again I could of used it

  2. I want to learn music one day, for now it's kinda impossible

  3. Been playing drums for 11 years and just started piano so it's cool to see this.

  4. I can't read music sadly. I play a lot of instruments though. Thanks for posting this as I have been playing piano a little bit lately.

  5. Bali Hai brings back some memories! I remember being part of the pit orchestra for South Pacific.

  6. Some interesting stuff, I've been wanting to learn some piano for years now but I've never found the time

  7. as someone who was very successful with instruments throughout junior high and high school, this is a bit advanced and fascinating.

  8. the interval identification link was incredible. thanks.

  9. Interesting post! I took like 4 music theory classes in high school and loved them, though i cant play any instrument

  10. Wish i could play an instrument :) nice post !

  11. Thank you for sharing this theory with us :) I really like the way you use popular songs to help indentifying intervals.

  12. Wow, this brought me back to music class. You did a really good job explaining everything in quick format. Keep it up!

  13. I didn't realize music was that in-depth.

  14. Ctrl+B, I may need this when I finally get around to learning!

  15. there is no way i'd be able to remember this. i'll just stick to singing

  16. Duuhh, I wish I could wrap my head around this...

  17. I need time to study this.. All I do is play a few riffs on mah guitar :/