In this lesson, I’ll be showing you the difference between the flat-third and the sharp-second.
If you’ve been around musicians, you must have heard terms like the “flat-third” and the “sharp-second” and sometimes you’ll hear the same terms as follows:
The flat-three
The sharp-second
…and it doesn’t matter if you say “flat-third” or “flat-three” because they all have the same meaning.
But in this lesson, we’ll stick to the flat-third and the sharp-second.
“Dr. Pokey! What Is The Flat-Third?”
Intervals are determined in music using the major scale as a reference.
For example, in the C major scale:
C is the first
D is the second
E is the third
F is the fourth
G is the fifth
A is the sixth
B is the seventh
C is also the eighth (aka – “octave”)
So, when you hear the flat-third, that presupposes that there’s a third and a good way to start is to determine what the third is.
From the C major scale, the third is E:
…and that means that from C:
…the E note is the third tone and as you can see, from C to E:
C (1), D (2), E (3)
…encompasses three alphabet letters.
“Now That We Have The Third Figured Out, What Is The Flat-Third?”
Lowering the third tone of the major scale by a half-step produces the flat-third.
So, if we have E:
….as the third of C:
…all we have to do is to lower the E (by a chromatic half-step) to Eb:
…and that’s it — Eb is the flat-third of C.
Attention: While lowering the third by a half-step, you have to make sure it’s a chromatic half-step. Learn more about chromatic half-steps here.
If you want to find the flat-third of any note, play the major scale of that note, and then go ahead and lower the third tone of the major scale by a half-step — a chromatic half-step.
The Sharp-Second — Defined
If you know the flat-third, understanding the sharp-second should be a walk in the park for you and this is because the way to go about the sharp-second is similar to what we did on the flat third.
“So, How Is The Sharp-Second Formed?”
The sharp-second is formed by the major scale as well and all you have to do is to determine the second tone of the major scale, and then raise it by a chromatic half-step.
Using the C major scale:
…we have D as the second tone of the scale (or simply the second):
Raising the second by a half-step (chromatic half-step):
…produces D#:
…and that’s the sharp-second.
So, if someone walks up to you and asks you what the sharp-second of C is, what would you answer?
Well, the answer is D#:
First of all, you already should know that D is the second tone of the C major scale and raising D by a chromatic half-step produces D#:
…which is the sharp-second.
“Wait A Minute!”
Can you see that there’s a relationship between the flat-third and the sharp-second?
Yes! Starting from C:
…here’s the flat-third and sharp-second:
The flat-third (Eb):
The sharp-second (D#):
…and both notes have something in common and that’s what I’ll show you in the next segment.
The Relationship Between The Flat-Third And The Sharp-Second
The flat-third and sharp-second are related in many ways and in this segment I’ll be showing you the similarities and differences between them.
Let’s start with the similarities.
The Similarities Between The Flat-Third And The Sharp-Second
If your eyes are closed and someone plays the sharp-second, it’s possible to erroneously perceive it as the flat-third and this is because of the enharmonic equivalence between D# (the sharp-second) and Eb (the flat third):
D#:
Eb:
With your eyes closed or open, you can’t tell the difference between D# and Eb (notes) until they are spelled.
So, in the C minor chord:
…where you have the minor third interval (C-Eb):
If you replace the Eb with D#:
…you’ll have C-D#-G:
…which would sound just like the C minor chord:
…but that would be a wrong spelling of the chord.
In a nutshell, the flat-third sounds like the sharp-second.
“Here’s Another Similarity…”
Between the first tone and either of the flat-third or sharp-second consists of three half-steps each.
C to Eb (a flat-third):
…consists of three half-steps.C to D# (a sharp-second):
…consists of three half-steps.
So, it doesn’t matter whether you’re playing the flat-third or the flat-second, each of them are three half steps from the first tone.
