If you're interested in understanding the basics of music theory and the nuances of music grammar you'll need to know how to correctly "spell" the various major scales. The resources on this page should help you learn to do so.
With the interactive musical slider ruler provided here, and the discussions below, you'll be able determine the letter names of the notes of any major scale. So let's take a detailed look at the major scale, and how to use this slide ruler above.
All major scales produces the sound of "do, re mi ..." In other words, they all conform to the the same formula— they share the same pattern of intervals between notes.
The formula for a major scale is: W W 1/2 W W W 1/2
The major scale formula is the core defining structure throughout western music theory. All chords and scales reference the major scale, and are defined in relation to it. In other words, their formulas are some sort of variation or deviation from the major scale formula.
The intervals of the major scale formula determine letter spelling of the fifteen major scales in common usage. These share the same formula, and simply have different roots—and they are the basis for the fifteen keys. Glossary note: The root is the starting point of the scale, aka the letter name of the scale, such as: A or Bb, B, C, C# ...
Regarding its impact on music notation, the major scale's formula defines the fifteen pragmatic key signatures found on the Cycle of 5ths.
You can start a major scale on any note. The starting note is referred to as the "root" or "name" of the major scale. The commonly accepted notes are A, Bb, B, C, C#/Db, D, Eb, E, F, F#/Gb, G, G#/Ab.
NOTE: The list above does not include other logical possible roots (A#, B# D# and E#and Fb) that are not pragmatic, that are considered illegitimate, because these exit the accepted Cycle of 5ths, and take us into the conceptual spiral of 5ths, which requires fanciful key signatures with double sharps or double flats, triple sharps and triple flats, and so on, into a spiral of increasing complexity and reduced practicality.
This side comment is intended for those "in the know" and to provide a gentle heads up. There are logical possibilities in music that are omitted because they lead to structures that are more complicated than pragmatic. Here's an analogy from fractions: we could write the fraction 13/4, but it's more easily comprehended when reduced to 3 1/4 or 3.25. So too in music, a certain level of simplicity is advised and adhered to.
The slide ruler illustrates and illuminates the basic concepts of scale construction and scale degree naming. However, as with all simple musical slide rulers, the correct answer is not a simple "lookup".
When there are two possible names for a note (i.e. enharmonics) you must make a grammatical decision. The rules for choosing the correct name are explained below. (Glossary note: An enharmonic is a musical synonym—an alternate name for the same sound, whether a note, chord, mode. For instance F# is enharmonic for Gb—both names refer to the same pitch. A D6 chord and a Bm7/D chord are enharmonic because they contain exactly the same notes. There are rules of grammar and notation that usually determine which "pronuciation" is correct, but sometimes it's up for debate.
Before proceeding, it bears mentioning. There are pros and cons to using a slide ruler. If it illuminates your understanding to a point where you no longer need rely on it, it has served its purpose well. Nevertheless a musical slide rule is handy when you're stuck or not feeling 100% sharp. And it can be a vital resource for anyone learning about music. But, as mentioned, most slide musical slide rulers require some level of interpretation; without interpretation they produce incorrect or grammatically marred information. So be mindful when using one, and be ware of the various edges where answers may fray into grammatical disarray.
For anyone interested in exploring beyond the major scale, you'll find an extensive listing of chord formulas and scale formulas at Sound Thinking—an interactive chord and scale encyclopedia for stringed instruments. You can use Sound Thinking to display dozens of correctly spelled chords and scales, in any key. Additionally it helps people visualize and explore the chords and scales on stringed instrument.
The slide ruler on this page initially displays the C major scale:
C D E F G A B
Arrows point upward from each scale degree (1st, 2nd 3rd, etc.) to the corresponding letter names (C, D, E ...) In other words, the 1st degree of the C scale is C, the 2nd degree is D, the 3rd degree is E ...
C is the simplest scale to spell, as you can see, because it has no sharps or flats. All other scales with have at least one sharp or one flat.
D E F# G A B C#
Although the slide ruler affords all the necessary information, in order to correctly "spell" the scale according to the rules of musical grammar you'll usually need to make some decisions. The C Major scale is the only scale that contains no sharps or flats. You'll see that the other modes of the C major scale, such as the A minor scale, also have no sharps for flats.
When you have the choice of a sharp name or a flat name (for instance, A#/Bb, C#/Db, D#,Eb, F#/Gb, G#/Ab), the general rules are:
This slide ruler is a tool that affords the answer for you, but it's wise to understand why these answers are correct. The following section will explain why.
If you are new to music, music notation, and music theory, you'll need to grapple with some basic concepts:
1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 4, 5, 6, 7, 1, 2, 3...
Here's an example of enharmonic note naming.
There is a note between F and G, but it has no letter name of it's own. The possible names are F# or Gb. Out of context either name will identify the pitch of the note. But in the context of a key, scale or chord, when confronted with an enharmonic choice like "F#"verses "Gb" you must decide which letter name to choose.
You'll can always determine correct answer if you consider the degree of the scale. If the degree of the scale is a 6th, then you must choose the letter that is the 6th letter of the scale. Simple as that.
Here are two examples:
You can use this slide ruler to spell the notes of any triad (major, minor, augmented or diminished) or dominant 7th chord (major 7, minor7, dominant 7 or diminished 7). You simply need to know the formulas for chord formulas.
The formula for a major chord is 1, 3, 5, therefore
a C major chord is C E G
a D major chord is D F# A
The formula for a minor chord is 1, b3, 5, therefore:
a C major chord is C Eb G
a D major chord is D F A
The formula for a dominant 7 chord is 1, 3, 5, b7, therefore:
a C7 chord is C Eb G Bb
a D7 chord is D F A C
Sound Thinking contains an extensive list of chord formulas and scale formulas.
More information about transposing at Key Switch
While a physical musical slide ruler can provide lots of answers, inevitably it will require some attention and decision making on your part. Slide rulers also allow choices you "shouldn't" make, such as choosing A# for the root of a key; while the key of A# is theoretically viable, and it's covered in the Spiral of 5ths, it is not a member of the Cycle of 5ths because it is not a normal key signature used in music notation—the reason for its exclusion is that it has double sharps in the key signature,and there's always a simpler alternative; in this case Bb.
Furthermore, a simple slide ruler cannot be entirely accurate. In the case of A#, this slide ruler does not show F##, C##, and G##. One could argue this is a moot point because, as mentioned, you should choose A# for the root of a scale. However, A# maybe an legitimate root for a chord! But these types of rulers will not help you spell chords with "out of gamut" roots like A#.
In the future I'll create another slide ruler that intelligently shows the correct letters names for any scale or chord. Part of the purpose here is to demonstrate that the limitations that all musical slide rulers share. (Read more ..."
For detailed information about scale formulas, chord formulas and the correct spelling of those in any key, see Sound Thinking.