# Determining closest key when primary contributing factors are shared among keys

Given a construct of intervals as follows:

1,#2,3,4,5,6,b7 (Dominant #2 first position)

For the purpose of general notation, as the #2 is equivalent to a b3 and the 3rd is still present, would this be classified as a major key with the raised second as the accidental since attempting to classify it as a minor would leave you without the second interval? As I understand it, your general key is derived by the root triad at the first tone. However if you have both 3rds present, is it a matter of first 3rd reached in the interval stack that determines key?

Given that I would assume a Dorian b4 is minor even though the b4 falls upon the major interval and using it in any other way effectively negates the 4th.

1,2,b3,b4,5,6,b7

Would the same logic apply for 8 tone Spanish?

1,b2,b3,3,4,b5,b6,b7

Am I incorrect in these assumptions?

When talking about what composes of a scale, letter name and interval matter. In your first example although the enharmonic equivalent of #2 is a b3, you would not look at it that way in the context of a scale.

If you built the scale off C you would get:

```C  D#  E  F  G  A  Bb
```

Again while D# and Eb are enharmonic equivalents the fact that you are using the D# as the basis of the scale means that you would not think of it as a 3rd of C hence the only third in this would be E.

Same goes for your second example which built on C would be:

```C  D  Eb  Fb  G  A  Bb
```

While Fb and E are enharmonic equivalents the fact that you are using the Fb as the basis of the scale means that you would not think of it as a 3rd of C hence the only third in this scale would be Eb.

The last is a little more complicated. Since we are trying to fit 8 notes into a scale when we typically have 7 there will end up being one note that can be viewed as just a chromatic passing tone in the scale construction. Let's look at the last scale built in C:

```C  Db  Eb E  F  Gb  Ab  Bb
```

You can see in the Eb, E, F the E is sandwiched inbetween. This means that in most cases it will be more of a passing tone than anything else thus the minor third will be more prevalent.

• Dom, thank you. Just to flip the script slightly and apply this to a minor key to see if I am approaching this correctly... With an Alt @5 bb7 construct of 1,b2,b3,b4,5,b6,bb7. That is minor as b4 becoming the enharmonic of 3 is 'intent' to modify the 4th where if I stated 1,b2,b3,3,5,b6,bb7 (odd I know, just trying to come up with an example) then I was really going for a major key, dropping the 4th, and adding a passing tone in the use of b3. Correct? Oct 25, 2015 at 21:36
• @ceearrtee not quite as the big difference is you only have 7 notes. The chromatic aspect only applies when there are more than 7 notes. It would sill be viewed as a b4 because you don't have a fourth.
– Dom
Oct 25, 2015 at 22:03