A Note is a frequency. We assign notes letters from A-G (igonoring sharps and flats.) For example The frequency 440 is Concert A (A4), the note they play in the orchestra when they tune up before they start.
They were already tuned when they came out but they do it anyways.
If you double the frequency of a note your brain will connect the two notes as the same but up some distance. We call distance octave. They call it an octave because there are eight notes in the major scale, but we don't know about that yet in this bish.
Humans can hear between 20 Hz and 20 kHz. So all the A's you can hear are:
| Note | Frequency |
|---|---|
| A9 | 14080.00 |
| A8 | 7040.00 |
| A7 | 3520.00 |
| A5 | 880.00 |
| A4 | 440.00 |
| A3 | 220.00 |
| A0 | 27.50 |
| A2 | 110.00 |
| A1 | 55.00 |
Unfun fact: We sample audio recordings at 44khz so that we double the chance of detecting an audio impluse. Shannon's Information Theory
These frequencies are standardized like metric. We could have decided to start anywhere and double the values to get our octave range.
In western music (we say western but it's really only different in India) we devide each octave into 12 notes. We call this the chromatic scale (maybe it's like all the colors).
Not to harp on it but in India they do some crazy shit with like quarter steps or something I dunno it's cultural.
E|--------------------------------------------
B|--------------------------------------------
G|--------------------------------------------
D|--------------------------------------------
A|--------------------------------------------
E|--0--1--2--3--4--5--6--7--8--9--10--11--12--
E F F# G G# A A# B C C# D D# E
But this astehtically sounds like shit so we have to do something with those 12 tones to make music.
99% of Western music is based on the major scale (Let it Be. The Blues, The Star Spangled Banner. All Lithurgical Music.) There are other scales (Arabian Nights from Alladen and Bottoms up by Trey Songz and Nikki Minaj are in a Harmonic Minor for instance.)
The Major Scale Sounds Like This
There are eight notes in the major scale. Some of them are whole steps (two half steps on the chromatic scale) and some of them are half steps.
Before we talked about 440hz being called A4 in like ISO and NIST. The reality is since our musical system is based on doubling frequencies, calling notes by letters and frequencies is a convention to get everyone on the same page. For chromatic, major, any scales we can talk about notes and intervals independent of their actual frequencies.
Some ways that we do that are:
- Letters: C D E F G A B C
- Numbers: calling the notes by their intervals. 1 is our root, 2 is a whole step about that and so on (1 2 3 4 5 6 7 8) (Root, whole step, whole step, half step, whole step, whole step, whole step, octave)
- Solfège
Do Re Mi Fa So La Ti Dolike fucking Sound of Music
In reality there are notes with defined frequencies, those notes form Keys, and we generally agree to tune our instruments around those frequencies.
Guitars are tuned to make chords, but their strings are set five whole notes apart and can help us thing about how the major scale works. Since guitar frets are in half steps we can play the whole scale on one string
E|--------------------------------------------
B|--------------------------------------------
G|--------------------------------------------
D|--------------------------------------------
A|--------------------------------------------
E|--0--1--2--3--4--5--6--7--8--9--10--11--12--
E F# G# A B C# D# E Again
But it's faster to move our fingers in one position than slide around the fret board.
So instead we play the major scale across three strings:
The F# Major Scale (to show the fingering and the scale with the most fucking sharps)
E|--------------------------
B|--------------------------
G|--------------------------
D|-----------------1--3--4--
A|--------1--2--4-----------
E|--2--4--------------------
F# G# A# B C# D# F F#
1 2 3 4 5 6 7 8
Do Re Mi Fa So La Ti Do
Chords are multiple notes played together. If you played any random notes together it would sound like ass, so instead we try to find notes that sound good together.
Chords are defined off of a starting note with some interval notes on top of them. The most common chords, the major triads, are defined as the root note, the 3rd note in the major scale, and the 5th note in the major scale. We denote those chords with their letter (C E A) or when talking about arbitrary intervals with a capital roman numeral (I IV V)
C Major: C E G (C1 3 5)
E Major: E G# B (E1 3 5)
A Major: A C# E (A1 3 5)
Sometimes we need music to sound sad. One way to do that is taking the third note in a major chord and moving it down a half step. We denote those chords with either an m (eg Cm) or a lower case roman numeral (ii iii vi)
C Minor: C Eb G (C1 3b 5)
Sometimes we need music to sound sad and also spooky. To do that we can drop our third and our fifth a half step. We denote those chords as dim (ie Cdim) or with the degrees circle that I'm not gonna look up the unicode for.
C Minor: C Eb G (C1 3b 5b)
Almost all music (except Hallelujah, Take me to Church, and Interlude from Home.) make use of a common set of triads. These triads are based on spacing our notes two whole steps apart at the root and then moving that finger position up one whole steps. While confusing the result is the basis of all popular music:
| Interval | Chord | Notes |
|---|---|---|
| 1 | C Major | C E G |
| 2 | D Minor | D F A |
| 3 | E Minor | E G B |
| 4 | F Major | F A C |
| 5 | G Major | G B D |
| 6 | A Minor | A C E |
| 7 | B Diminished | B D F |
Regardless of what note we start on most popular music follows similar patterns
Ooh this shit is lame
- Link
- Key: D Major (D is the root note)
- Chord Progression: D -> A -> Bm -> F#m -> G -> D -> G -> A
- Interval Progression: Major 1, Major 5, Minor 6, Minor 3, Major 4, Major 5, Major 1.
Basically every pop song.
- Link
- Key: C Major (really any key)
- Chord Progression C major -> A minor -> F Major -> G Major