# Are melodic intervals in relation to key or simply the last played notes?

Is the concept of 'intervals' in this sense any note in relation to the tonic note of the key, (whether that tonic note is being played at the time or not), or are melodic intervals just the immediate notes preceding the current note, regardless of key or other context?

So for example, in the key of C major...

if you play an F note, then a G note... does that mean this interval is the perfect second in between these two notes?

Or are these notes intervallic in relation to the tonic note of C?

In other words, is this F to G in the key of C a major second interval, or is this a perfect fourth, then a perfect fifth (C-F C-G)?

An interval is the distance between any two named pitches, regardless of context. So, F and G are a major second apart from each other no matter what context they appear in.

In a melodic interval the notes sound consecutively.

In a harmonic interval the notes sound simultaneously.

In terms of their relationship to a tonic pitch, that is thought of less in terms of interval or more in terms of the functional relationship. For example, `B` in the key of `C major` is called the "leading tone", because its function "leads" upward to the tonic. On the other hand, `B` in the key of `D major` is the "submediant", one role of which is as the tonic of the relative minor scale.

### Examples

``````X:0
T:F and G in the key of C
T:F and G are a major second apart
K:C
M:C
L:1/4
C"_P4"xF"_M2"xG"_P5"xC
``````
``````X:0
T:F and G in the key of A
T:F and G are still a major second apart
K:A
M:C
L:1/4
C"_d4"x=F"_M2"x=G"_d5"xC
``````
``````X:0
T:F and G as a melodic interval
K:C
M:C
L:1/4
C"_P4"xF"_M2"xG"_P5"xC
``````
``````X:0
T:F and G as a harmonic interval
K:C
M:C
L:1/4
C"_M2"[FG]2C
``````
• Disagree with the 1st statement! Call that pitch E# instead of F, and it's a different interval. It's all in the names, not the pitches!
– Tim
Oct 1, 2020 at 7:55
• @Tim Good point. Does my edit sufficiently clarify? Oct 1, 2020 at 7:57
• Clarification accepted !
– Tim
Oct 1, 2020 at 8:03
• Okay, makes sense. Thanks!... So then I'm curious whether or not pitches would still have a relationship with the key tonic? Whether or not its an official idea or not, what do you guys think? Oct 1, 2020 at 17:41
• @SeanStewart I've edited to address the relationship to the tonic. Oct 1, 2020 at 19:14

Your question: are the tones F and G referred to C an interval called the 4th respectively the 5th or can they also be related to each other?

Interval means the difference - or better: the distance - to the root of the scale, but also to the root of the chord and even the distance between any two or more tones, sounding together as “Klang” or as sequence of tones in a melody.

You are correct: F is the 4th and G the 5th regarding the distance (=interval) to C and and there is a major second between F and G.

• Disagree! 'Distance to the root of the scale'. There's no reason to involve a scale of any kind when calculating intervals - in fact, it can confuse the issue.
– Tim
Oct 1, 2020 at 7:42
• The “names of the degrees” are (Roman numbers!) referring to the root: the 5th (=V), the prime = I etc. It makes sense to differentiate the degree intervals by R.N. from the chord intervals by Arabic numbers like the interval steps between the melody tones. Oct 1, 2020 at 9:29
• True, but my point is that there is no need to consider the lower note to be the root of a particular scale. Not thinking about RN at all.
– Tim
Oct 1, 2020 at 10:54
• @Tim when considering the identity of melodic notes, i.e. what the melody is and how it differs from other melodies, the distance to a tonic is important as well as inter-note steps. C-D-E with a previously established C tonic is a different melody segment than C-D-E with F as the tonic. Assuming that that's just a part of a longer melody and something has already happened in the melody before the notes. Oct 1, 2020 at 17:33
• @piiperiReinstateMonica - of course it's going to have a different feel, but at the end of the day, those intervals are going to be called by the same names, and that's what this issue is about.
– Tim
Oct 1, 2020 at 18:14

Intervals are note specific. And not even pitch specific!

Obviously an interval is the 'space' between two notes - but those two notes could be found in different keys, so can't be key specific. Example: (yours) F>G is M2. Both F and G are in key C, and key F.

However, the key specific bit could be that certain notes are not in a particular key, or are usually sharp/flat in a particular key. But that's somewhat irrelevant, as an interval is that between two named notes.

You seem confused about inversions. The difference between P4 and P5 is always M2 - there's no need to reference your F and G in key C - or any other key.

For simplicity's sake, intervals are found by counting (up works better). Any letter name to any other letter name (higher) provides the number of that interval. So, C>A. C D E F G A. 6 letter names = a sixth - of some sort.

Then we need to qualify what sort of 6th. Maybe that's over answering the question as it stands?

EDIT: one can use the root of a key to determine certain intervals, but not all. For example, in key C major, C>D=M2, C>E=M3, C>F=P4, C>G=P5, C>A=M6, C>B=M7. However, all those intervals will be called what they're called when found in any key. Confusing? A little.