Figuring out Key Signatures

[spitllama]

I think I struggle with this the most out of all the parts of transcribing. First of all I have no clue if pieces should be sharps or flats throughout, and then on some pieces I'll find that certain sharps reoccur, but they're so far from each other (ex. F# and A# or Gb and Bb) that I'd have more accidentals to account for the notes between, than saving with the new key signature.

Specifically, these pieces:

Princess Shroob Battle (1st)
[ZIP]

I see an F# and A# reoccurring..

King Dedede's Theme
[ZIP]

I... dont' even know

The Distortion World
[ZIP]

[Bespinben]

I asked pumpy_heart a few questions about key signatures myself awhile back. He's very knowledgeable - here's what he said:

For the easy way, take the major key signature and go down two steps from the name of that key signature. So for Ab Major, the minor key associated with that key signature is F minor. Vice versa, take the minor chord and go up two steps to find what the key should be. So for A minor, up two steps is C, so the key sig would be C major.

For the real way to know, the third of the tonic triad determines what the key is. The tonic triad is typically what the piece begins, centers, and ends on. If a piece begins on an G# minor chord and ends on a G# minor chord and appears a few times through the piece, the tonic triad is 99% of the time G# minor. So a major tonic triad determines what the key signature should be; ergo an Eb major tonic triad should have an Eb key signature. If a tonic triad is minor, this also determines what the key should be. Take the third of the tonic triad, as in your piece C Eb G, and that is your key. If this is the main key throughout the piece, as in your piece, then the entire piece is in C minor, meaning the key signature is based on Eb major, meaning that there are 3 flats in the key signature.

A key signature shouldn't be seen as what defines the key. Rather, the note pitches define the key signature.

One last thing to point out, minor keys typically have (at least) one chromatically altered note. This would be scale degree 7 (ti in solfege, subtonic (whole step below from tonic), the note directly below tonic). This note is usually raised to lead, created a stronger motion, towards tonic. This is now called a leading tone. So in A minor, G would typically be changed to G# to create a stronger movement towards A, tonic. This already exists in major, as in the key of G, F# is already raised, becoming a leading tone to G. Another thing the raising of scale degree 7 creates is a major chord built on scale degree 5 (dominant, sol in solfege). The relationship of tonic to dominant is the strongest in all Western music. In major keys, tonic and dominant are both major; for example, in the key of G, G and D are both major chords. The D major triad, containing the leading tone F# in it's triad (the notes in the triad), leads to G due to that half step relationship between the two notes. Minor keys alter scale degree 7 to create this strong effect borrowed from the Major keys.

Play (major chords) C-G-C-G-C on the piano to see what I mean. For minor, change the C major chord to a C minor chord and do the same; Cm-G-Cm-G-Cm.

I added the last because you will definitely need to know that as well when determining what key signature to use.

Also, if the minor key is flat, Bb minor, the leading tone is shown with a natural sign (as opposed to Bbb, which shows confusion of tonic). If the minor key is natural, the leading tone is shown with a sharp; G minor's leading tone is always spelled F#.  If the minor key is sharp, G# minor, the leading tone is spelled with a double sharp (as opposed to G natural, use Fx).

And that last tip let's you know how to chromatically spell the leading tone notes.

Whew. If I typo'd or there's something you don't understand, ask away. On anything musical, that is haha.