100% you could do that to help.
Cheers 
| Richard_close2u | Community Moderator, Official Guide, JustinGuitar Approved Teacher
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I get how the trick works but, I’m with you Flick, I don’t know how to apply it to sharp keys. For example D#
D#, E#, G, G#, A#, B#, D.
So, D# has 5 sharps. How do I get that from Mr Cato’s system? It appears that the key with 5 sharps is B?
There must be some piece of the puzzle that I’m missing.
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Hi Phillip,
“In real life”, you’ll need sharp keys very rarely. The sole exception is F# major which has only 1 natural note (B) in it.
From C# major onwards, the cycle starts again and the scale notes will be 1 semitone higher than in their natural counterparts. E.g. the notes of the D# major scale are the same as those of D major, only 1 semitone higher. A double sharp is used when an already sharpened note is raised by another semitone.
Also, you have to have each “letter” only once in a scale, so no G and G# in the same scale or jumps like B#-D.
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Hey Phillip,
The key of D#Major has 5 sharps, and 2 double sharps.
Ie.
D#, E#, F##, G#, A#, B#, C##
It is largely a theoretical key, and would not usually be used in practice. Eb Major would be used instead.
Cheers, Shane
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I had a very similar realization just this week. How the sharp that get added to make the next scale is always a semitone below the key of that next scale. I was so happy about it that I just needed to make it into a diagram and figure out what was going on. I think it ended up exactly like what you mention.
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Thanks for pointing that out Michiel.
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@joselp Thanks for the tip. That is better than remembering a mnemonic and faster than my counting out the circle of fifths on my fingers 
I had never thought about the cycle of fifths as being sequential for every other letter.
I thought about it some more and saw another interesting fact:
The C D E are the white keys surrounding the 2 black keys on the piano keyboard.
Then the F G A B are the white key surrounding the 3 black keys on the piano keyboard.
With this fact and your tip I can easily remember and write out the 7 notes in the chart.
I also know the open notes on the guitar forward and backwards, so as @apropostt suggested I can think of the 2 thinnest (highest pitch) string barred at the first fret and name the notes going down in pitch for F C G D A E, and remember to add the B.
One other cool thing I noticed about @joselp ’s arrangement of the notes, If you think of the first line as notes on the thickest 6th string (and ignore the F note) and the second line as notes on the 5th string
6th string: F____G____A____B ————->G A B You have the 6 essential notes.
5th string: ___C____D____E ——-———>C D E
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Th;is is a great lesson on an easy easy to remember all the sharps and flats of the keys. I wasn’t planning on memorizing the complete major scale table so this will be useful (such as on the Grade 3 test).
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Hello @PJPro and welcome to the community.
For awkward keys, which you can figure out on paper but which you will likely not use in practice, there are several approaches.
D# is a key one semitone above D.
List the D major scale:
D major scale → D, E, F#, G, A, B, C#
Rewrite it with all notes raised by a semitone - but, crucially, maintaining the alphabetical list exactly the same.
D# major scale → D#, E#, F##, G#, A#, B#, C##
That is quite ugly isn’t it? Yet it exists in music.
You could do the same going in the opposite (flat) direction.
D major scale → D, E, F#, G, A, B, C#
Db major scale → Db, Eb, F, Gb, Ab, Bb, C
All notes lowered by one semitone.
Alternatively, you could use the circle of fifths which has all keys in all directions both sharp and flat. The Circle of Fifths Part 1 - where does it come from?
I hope that helps.
Cheers
| Richard_close2u | JustinGuitar Official Guide, Approved Teacher & Moderator
Just got to this lesson on the course but slightly confused. I can work out how to get the number of b’s and #'s in a key but not how then to get all the rest of the notes. See the example below:
So we know that there are 2#'s in the key of D but it’s a big jump to then know the rest of the notes, or is this just a case of using the Major Scales worksheet from the earlier lesson? At this stage there is no way that I can remember all notes in each key.
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Hi Stuart,
I usually use the major scale formula (TTSTTTS, see the lesson and the worksheet) plus a few hints, like:
- Degree VII is always a semitone lower than the root note (e.g. C# in D major)
- “New” sharps appear on degree VII
- Degrees III and V are in the major chord formula as well (e.g. D - F# - A)
As for the order in which sharps and flats appear, I’d suggest to check out @Richard_close2u’s extra material on the circle of fifths as it’s really well-written and informative, starting with all the basics you need to know. So, in time, you’ll be able to tell things like which major scales may have an A# in them.
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@Stuartw it’s easy. Every major scale has 7 notes A B C D E F G.
Using Mr Cato’s chart you know in the key of D major the C and F are sharp. So starting with the root D the note of the D major scale are D E F# G A B C# D.
Using Mr Cato’s chart write out the notes of the A major scale.
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It is now!! Went back and had another look at this and it’s a whole lot clearer.
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Hi first post so please don’t shoot me down, I find playing the chords in order with C being 0, G being 1, D being 2 , A being 3 etc , really helped me visualise this. I know F is that start point and then I just add in the letter of the chord sharps I’ve already played. The visualisation on the keyboard cracked this in a couple of days for me. Trickier with the flats but play in reverse and add in the next chord. (ignoring the F, as F is always a problem! ) , I hope that helps someone.
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Im lucky enough to have a wife who has over 20 years of classical piano training. i’ve been learning guitar from you over the last year and now these fascinating theory classes have sparked some funny memories for my wife when she was a little girl.
When she was 7 years old her piano teacher told her and her classmates to come up with their own mnemonics to remember the order of the sharps.
Long story short. Her older classmates all came up with some fancy sentences for the FCGDAEB layout. When it was her turn to say how she remembered she just blurted out…
“FUH, CUH, GUH, DUH, AH, EE, BUH!”
Her classical piano teacher couldn’t hold it together and just burst out laughing.
Now my wife and I share this strange alien language with each other when we randomly blurt out, FUH, CUH, GUH, DUH, AH, EE, BUH!"
I’m loving all of your classes, thanks for putting all this together Justin!
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It’s that last step that usually gives people brain-strain! I used to find it difficult as well, but you’ll be amazed at how quickly you will internalise the most commonly-used keys, and will know that, for example, D has two sharps - F# and C# - or that Ab has four flats (Bb, Eb, Ab and Db). You won’t have to work it out; you’ll just know.
Yep. That is simply slick as a whistle. And it works! Even my elderly brain can wrap itself around that concept. Way cool. I guess my next couple of practice sessions will be internalizing Mr. Cato’s diagram.
Finicky Chicks Get Darn Annoyed Eating Baloney
Thanks!
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This is an amazing lesson! Been working on memorizing this and i stumbled on an interesting observation that i think i’m going to use to remember this. I observed that if i memorize just the right side of Mr. Cato’s diagram i can work out the equivalent flat and sharp key signatures. E.g. Memorize the A major using Mr. Cato’s diagram.
A maj = A, B, C#, D, E, F#, G#
A# maj = Replace all sharps in A maj with natural and replace all naturals with sharps = A#, B#, C, D#, E#, F, G
Ab maj = Replace all sharps in A maj with natural and replace all naturals with flats = Ab, Bb, C, Db, Eb, F,G
Only 2 exceptions to this trick
F# maj = The Bb in F maj becomes B natural in F# maj
Fb maj = The Bb in F major becomes a Bbb double flat in Fb maj
It was one of those amazing light bulb moments when i stumbled on this :- )
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Lots of good replies. I think with such a heady topic, everyone is going to have different things that clicks. I had a good mnemonic device, but this works better and is more instantly obtainable by my brain because it matches up with the power chord root notes I’ve already memorized without having another mnemonic to remember. Seeing the letters separated like in your image (as if it’s the 6th and 5th strings) made this click for me. Thank you.
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So, I have a mnemonic, I have Mr. Cato’s diagram memorized and I can mostly go through the diagram in my head to name the notes of each key. I can definitely do it if I draw out the diagram. Since this is the only part about module 3 that I’m still working on, I’m wondering if it’s a good time to move to module 4 or should I be able to name the notes in each key straight away without thinking about or drawing a diagram? I want to make sure my foundation is solid but also want to make sure I’m not treading water here longer than I should.
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About F# and C#: Mr Catos method works for these too, however we have to consider their respective enharmonic equivalents. For F# we have Gb. So, we can write Gb scale using Cato and then write the equivalents for flat notes. We end up with B as the only natural note, which is consistent with the major scale table and Formula.
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