ELI5, why are the musical notes represented by letters in some places (C-D-E-F-G-A-B), but in others by their sound (do-re-mi-fa-sol-la-si-do) ?



I’m from Mexico and the way I learned the musical notes was by their sound, however some friends from other places learned the notes with letters.

In: Other

Do-re-me and such are used to show a notes position in a scale, for example in a C major scale, C is do, D is re. A B C and so-on are the exact note names, corresponding to a specific pitch

Do re mi etc is not as awkward to sing as c d e f g a b. But the letters are used for musical notation, which is pretty complex if you really get into it, so it makes sense they picked the first letters of the alphabet for that.


They aren’t (necessarily) the same thing. The do-re-mi (solfège) system does not (generally) fix “do” to a particular note – it’s just a scale of set intervals (tones and semitones). You could start it at C, or D, or A, or G, or any note you choose. In other words, it depends on the key you’re in. Solfège is useful to do things like sight reading, because if you’ve memorized the do-re-mi scale then you know what different intervals (e.g. thirds, fifths) sound like, which is enough to figure out what a piece of music sounds like from sheet music (if you also know the key).

The letter system, on the other hand, assigns names to particular frequencies of sound. Middle C, for instance, in standard tuning, is a frequency of 261.626 Hz. The C one octave above that is exactly double that frequency, and the C one octave below is exactly half, and so forth. It’s still a system that is relative to a reference, because you have to pick one frequency that you align everything else to. The most common standard is to pick A4 (A above middle C) = 440 Hz. Other standards may put A4 at slightly different frequencies, but it’s not like solfège where you can set ‘do’ to be literally any note and start the scale from there.

Now there is something called “fixed-do” solfège which is used in a number of places (including Mexico), where they decide that do = C. In this case, the do-re-mi naming system is equivalent to the letter-based system, and it’s just a matter of preference (you could equally refer to the notes by colors, for instance – it’s arbitrary). Personally I would say it makes more sense to use separate naming schemes for relative and absolute scales, but there you have it.

The do re mi method (solfége) is for teaching pitches for people who haven’t much music education. As the student grasps more and more theory they move on from the solfége to actual note names and locations on the staff.

I believe these two things are not the same actually. While C-D-E etc. are absolute note values (a certain pitch), the do-re-mi scale is relative to a base tone. So if you start a major scale from G, then do will be G, re will be A, mi will be B etc.

So one denotes fixed pitches, while the other denotes relative pitches to a base tone.

We’re really talking about two separate tools used in music and singing. Do-re-mi is never used to *notate,* it’s only real use is *calibration*.

Professionally, the do-re-mi pattern is really only ever used in a practical setting as a *vocal warm up.*

It isn’t fixed to any specific note on the scale, rather, it’s phonetically easy to sing and provides easy, common transitions between vocalized notes. This simply provides a starting point for calibrating your voice to an established musical key (and can be adapted to any major/minor key).

You can start the “do re mi” scale wherever you want. You can sing “do” in an F or in a C, that’s up to you as a singer to learn how to make that sound in the specific note you’re looking for.

It also helps your voice transition over the octave break. Finding and compensating for that break is pretty important, and the Do-Re-Mi scale helps make it easier.

The ABCD structure, on the other hand, is designed to give a universal method of notation to any particular tone. Because sound is quantifiable, we’ve figured out that it can be broken down into octaves and scales (and even these have shifted over the centuries). So we just needed a mathematical way to communicate said scales.

This is why we include sharps and flats in notated music, but you’ll never hear someone say “no, that’s a Mi-sharp.”

Typically, countries with a Romance language (like Mexico) use the “Fixed Do” system, in which each specific pitch has its own distinct solfege syllable (the note at 440 Hz is called La, for example). Countries with Germanic languages (including English) tend to use the letter names instead (440 Hz would be “A” instead of “La”).

I’m from the US where we use letters to refer to specific pitches, but we also use a form of Solfege to teach people to sing. The most popular method is called “Movable Do,” which would probably drive you crazy if you listened to it. In Movable Do, the pitch names that you are so familiar with aren’t assigned to the “correct” pitches; instead we call the first note of whatever scale is used “Do,” and assign the other pitches accordingly.

If you and I are both singing a piece written in C major (Do Mayor), we will be singing the same solfege syllables, but if the piece is in any* other key we will disagree. Your “Do” is what I call C, but my “Do” is determined by the context of the music. They say music is a universal language, but your solfege syllables actually do depend on your local language.

*I’m leaving out some nuances (Do-based minor vs La-based minor, for one) but we’ll get to those when you’re six or seven. Thanks for the question!

Other people have given great explanation, so this is just what I have to add:

The method most Americans use is called the Kodály method, named after Zoltán Kodály (not pronounced how you think). Kodály is who you have to thank for the [hand gestures](https://hungarytoday.hu/wp-content/uploads/2016/05/solfege_ladder.jpg) that go with the Solfège, but there’s a lot more than that.

If you want to describe the 3rd scale degree you’d say “Mi”. But what if we’re in a minor key. We can’t sacrifice the Tonic meaning of “Do”, so what do we say for a flat “Mi”? We say “Me” (pronounces ‘May’). Basically replace the vowel sound to any solfège syllable with the “e” and you get it’s flat form. What about sharp 4? “Fi”. It gets a little irregular though when you think “what’s the sharp third scale degree” or “what’s the flat second scale degree”, but what’s important is that now we have a way of expressing the melodic function of pitches without having to contextualize them by specifying key.

As for the origin of the Solfège syllables, it’s a really cool story. In the Middle Ages, long before we had modern tuning or theory or scales, people thought of scales in the context of the “[hexachord](https://en.m.wikipedia.org/wiki/Hexachord)” (“six notes”). Music theorists back then declared that pitches ought to be grouped in six, leading stepwise up, and the arrangement of these six pitches determined the mode (basically the church modes we know and love: Phrygian, Dorian, Hypodorian, etc).

There used to be no name for any of these pitches. Your choir director just told you “hey, this song’s in Lydian,” and would give you a note, and that’s where you start. But a dude named [Guido of Arezzo](https://en.m.wikipedia.org/wiki/Guido_of_Arezzo) decided it’d be easier for his choir to learn psalms if they had names for each of the notes. So he turned to a psalm called [Ut queant laxis](https://en.m.wikipedia.org/wiki/Ut_queant_laxis), which had a nifty trick where it began a phrase starting on the first pitch, and the next phrase began on the next pitch, then the third, fourth, etc, all the way up the hexachord. He took the first syllable of the first pitch of each phrase, and got:

“Ut, re, mi, fa, sol, la”

Now, back then they used the syllable “ut” instead of “do”. I’m not sure why we changed it, but I’m sure there is a wonderful anecdotal explanation behind it, but my best guess is that all the other syllables begin with a consonant, so they’re more articulated and easier to sing.

This system caught on, especially in the context where it began: the Roman Catholic Church. Because of this, the “fixed-do” method of Solfège being the actual names of notes exists mostly in countries with a catholic tradition, usually speaking *Roman*tic languages. And since it’s based on the hexachord, the seventh scale degree syllable was added later, which is why there’s disagreement between “Ti” and “Si”, and why in German they call B-flat “B,” and B natural “H”.

tl;dr: Kodály method differentiates between Solfège and letter names as well as giving Solfège for accidentals; origin of Solfège and Guido of Arezzo; musicology is cool you should study it.