Why are scales important for writing melodies?

I’m trying to wrap my head around the concept of tonality and how scales fit into it. From what I understand, the relationships between notes (intervals) is at the core of how we write melodies and why they make us feel the way we do. It also seems that scales are built on top of those relationships and then chords are built on top of those scales. I still feel like I’m missing something there. Does anyone else have some insight into this? Wouldn't it be easier to just base everything off of the chromatic scale instead of having a million different scales and chords? Every interval relationship is already in the chromatic scale, why do we need others??

To Simplify:

Tonality = Mood
Tempo = The speed in which the composition is played
Key = The note the song is built around
Scale = List of notes in that Key

In general it does not matter, because everything connects with each other. If you play by ear it doesn't make a difference, as long as you've mastered your instrument. However these things you talk about, is so others can read it and play your music. It makes it easier if there is some kind of system that helps to organize ideas and reproduce the composition.

CharlesRandolph wrote:To Simplify:

Tonality = Mood
Tempo = The speed in which the composition is played
Key = The note the song is built around
Scale = List of notes in that Key

In general it does not matter, because everything connects with each other. If you play by ear it doesn't make a difference, as long as you've mastered your instrument. However these things you talk about, is so others can read it and play your music. It makes it easier if there is some kind of system that helps to organize ideas and reproduce the composition.

If you hear a musical composition and none of the sounds clash, scales were used whether consciously or subconsciously by the musician(s). That being said, not all songs live in the same scale throughout the entirety of the piece. There are many techniques for switching both key and scale between measures and sometimes between frames within a measure.

As always though, if it sounds good.... do it.

hellnegative wrote:
If you hear a musical composition and none of the sounds clash, scales were used whether consciously or subconsciously by the musician(s).

Depends on the composer and composition because adding dissonance is a way to evoke emotion.

hellnegative wrote:That being said, not all songs live in the same scale throughout the entirety of the piece. There are many techniques for switching both key and scale between measures and sometimes between frames within a
measure.

Correct, many songs change Key and as well as Time signature, which is usually notated in the sheet music.

hellnegative wrote:As always though, if it sounds good.... do it.

I tend to lean toward: If it conveys the emotion, you're looking for. Do it! If it doesn't try something else.

Sorry if this post gets confusing, its hard to write all this down in one post and not stray away too far from the question in hand.


There may be 12 notes in the system but in most scales theres only 7 notes (and in pentatonic theres only 5).
Music is art but its also math, the relationship between the root note and what you stack on top of it is mathematical.
If we for simplicities sake take the example of the C major scale (all the white keys) you have the notes C D E F G A B (and then back to C). The note names themselves isnt what makes up a major scale, its the relationship to the root note - this is called an interval. in any major scale the intervals are - root, major 2nd, major 3rd, perfect 4th, perfect 5th, major 6th and major 7th.
To construction any given 3 note chord in the scale you need a root note, a 3rd and a 5th. And to construct the chords you simply just take a note (C), take two steps up in the scale (E), and then two more (G). C E G is the I (1st chord) in C major and since its constructed of a root note, a major third (4 semitones) and a perfect fifth (7 semitones) you get a C major chord.
If we were to start on the second scale note D and do the same thing you would get D F A which would be Root - minor third (the F is only 3 semi tones from the root compare to the 4 semi notes between C and E in the previous chord) and perfect fifth (7 semitones) makin this chord a D minor chord.
same can be done with all the notes in the C major scale. and in the end you would end up with 7 chords in C major being:
I - C Major - C - E - G (root - major 3rd, perfect 5th)
ii - D Minor - D - F - A (root - minor 3rd - perfect 5th)
iii - E Minor - E - G - B (root - minor 3rd - perfect 5th)
IV - F Major - F - A - C (root - major 3rd - perfec 5th)
V - G Major - G - B - D (root - major 3rd, perfect 5th)
vi - A Minor A - C - E (root - minor 3rd - perfect 5th)
vii° - B Diminished B - D - F (root - minor 3rd, dimished 5th which is 6 semitones)

What about minor keys? its the same! the key of A minor shares the exact same notes as C major (all white keys) and the exact same chords but starting on the A.
Am, Bdim, C, Dm, Em, F, G.
Its all about the relationship to the tonic (first note of the scale, the "home" note). Music is about tensions and release and it all relates to what feels like "home", which is often your one chord. The home chord in C major its C and in A minor its Amin.


So to sum this up scales and keys are the framework and "rules" for which music is built upon. Sure music is subjective and all but to break the rules i believe you first need to know them.

feel free to ask for clarifications and keep jammin.

Yes these are basics twelve-tone equal temperament, however thing do change when composing Microtonal music.

For me when I listen to my fav songs they tend to fall within a certain key or mood you might say. I think of scales as the type of scenery I want to paint with colors and strokes if I was a painter. As a dj scales of the songs I play would fit the set I want to play for the audience deep, soulful, lively, or hard as well as the tempo. One app that really help me realize scales, chords, melodies, voicing and modulation Was scaler 1 and now scaler 2. Both are eye openers and great composition and learning tools for beginners like myself.

Plus listening to music in general as a fan and digging guitar into the scales the original composers used. We all get influences from somewhere hence now not only sample the phrases from records but breakdown the scales, chords, progression and melodies too.

We still haven't figured out if this is a bot or not yet?

The account keeps making posts then never replies.

Chord progressions and scales compliment one another to make a composition.

When chosing a chord progression whether it's sad, happy, inspirational, dark, harmonic, cinematic etc scales will present its self to write melodies and counter melodies to help complete a well writen composition.

You make a chord progression with the notes you have chosen you will be able to find only the notes you can use which is the scale.

Hope the good answers weren't too late to help the OP with his homework.
There's a book of scales and modes of the world. Ravi Shankar explains the modes and scales in classical Indian music. Not that I remember. Anyway there's hundreds of scales. Some based on overtones, whatever that means. You can get in a rut with just one scale.
If OP wants to think only chromatic fine. You can follow the chromatic path, whatever that is.. For guitar or something it might help to know some chords