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I was going over the circle of fifths as part of theory, and I was trying to write out the G-flat key signature. I put the G-flat in where the red flat is in the image below, but I realized that the signature actually uses the G closer to middle C. Is there a reason why this is the case?

The key signature of six flats in treble clef, with the G-flat crossed out and rewritten (in red) in the first space above the staff.

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    Well, by using the G-flat highlighted in green, it keeps the pattern of the flat being one note lower than the note two before it. It also just looks nicer that way, in my opinion.
    – Jerry Cui
    Dec 27, 2023 at 23:17
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    @Aaron that's not what "begs the question" means. Dec 28, 2023 at 18:41
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    @CarlWitthoft Sure it is. It means that it brings up additional unasked questions. For example, your comment, since it doesn't address the OP and is directed specifically at me, begs the question of why you felt it imperative to post it.
    – Aaron
    Dec 28, 2023 at 21:20
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    @Aaron, and CarlWittholft, in case anyone really cares, I'd confirm Carl's remark that "begs the question" at least formerly meant "assume the conclusion", which is nearly opposite of its use today. :) But, well, even if usage doesn't determine "correctness", it manifestly ... reflects usage/understanding? :) Dec 28, 2023 at 21:31
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    @CarlWitthoft Well, I'm with you there. My pet peeves are "comprise", omitting the Oxford comma, and split infinitives. (Regrettably, the last time I looked up "comprise", it had become acceptable to use it as a synonym for "compose". I protest!) Now get off my lawn!
    – Aaron
    Dec 29, 2023 at 2:18

4 Answers 4

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Here's the layout for sharps and flats in the main clefs. Sometimes it can be justified by 'maintain the pattern' or 'keep it all in the stave'. But some decisions are just convention, Why A rather than B for treble clef sharps? Why aren't bass clef flats a mirror of bass clef sharps, rather than being allowed to fall off the bottom of the stave? I don't think 'why?' is going to get us very far here!

enter image description here

I don't think the convention is much disputed. Here's what Gould has to say.

enter image description here

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    This doesn't really answer the question. It just confirms that "that's how it is."
    – Aaron
    Dec 28, 2023 at 0:19
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    @Aaron "That's how it is" is the answer.
    – PiedPiper
    Dec 28, 2023 at 0:27
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    @PiedPiper Key signatures didn't evolve arbitrarily. "That's just how it is" is effectively the same as "I don't know."
    – Aaron
    Dec 28, 2023 at 1:03
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    This question reminds of the usual question that most math students ask at some point: why is the factorial of 0 equal to 1? And the answer is: it's convention! Asking why the convention is the way it is can bring insight, as in the question I linked. In this case (and unlike the math question I linked), I think that using a different convention will not change anything because the information will be the same, and the why of it doesn't seem as important. It's likely just a more intuitive or easy-to-the-eye notation Dec 28, 2023 at 1:20
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    @Laurence That is a motivation for the definition of n! and 0!, not the actual formal definition. Definitions in math are prepared around such intuitive concepts (counting, etc) but are worded in a very formal unambiguous way. We define n! as the product of the first n integers (for n>0). 0! is then set to 1 as a convention. In my opinion, the convention 0!=1 is used because many formulas that use n! (such as the Taylor series and the Binomial coefficients) still hold for n=0 with it. If it were more convenient to have 0!=0 in the formulas, motivations for that choice could be found, I think Dec 28, 2023 at 5:17
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Laurence’s answer has it all laid out. Sometimes the answer is simply: “Because that’s the way they did it a few hundred years ago and that’s the way we still do it”. However, there is a certain logic to it.

If you look beyond that you will see a certain patterns or hierarchies emerge. One pattern is that for flats it is always up a 4th then down a 5th. That creates the stair pattern we are all used to. For sharps it is down a 4th then up a 5th except for when it starts to get a bit high, then it’s down a 4th twice in a row (G#, D#, A#). Another thing is it never goes up or down two 5ths in a row. All this results in a clean and easily recognizable look for all the key signatures.

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    Bit like we don't count the dots on a die - it's the pattern that's recognised.
    – Tim
    Dec 28, 2023 at 9:28
  • @Tim That’s a good analogy. Dec 28, 2023 at 16:12
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The short answer is: it’s just the traditional way of laying out the key signature. Key signatures aren’t as much read as they are recognised — and messing with the normal arrangement is only going to mean that it would take slightly longer for the performer to recognise what the key signature is, and for no gain.


A more in-depth answer is that it looks much neater this way. Consider the conventional layout for the flat and sharp key signatures in the four clefs still in regular use today:

The key signature of seven flats and seven sharps in treble, alto, tenor, and bass clef.

The pattern for flats in the key signature is that they go: up a fourth, then down a fifth, and repeat. This simple pattern keeps the flats towards the middle of the staff, and can be applied to all the clefs. The only compromise is that F♭ appears in the first space below the staff for bass clef, (but seven flats is very rare).

If G-flat was up rather than down, it wouldn't work for tenor clef, as it’d require a leger line.


To keep the sharps of a key signature toward the middle of the staff, there is a different pattern (with two downs in a row), the sharps go: down a fourth, then up a fifth, down a fourth, and repeat. This keeps all the sharps near to the middle of the staff, with the compromise that G♯ occurs in the space above the staff in treble clef.

However, this sharps pattern doesn’t work for tenor clef (the rarest clef still in common use) — it would put the G♯ on a leger line. So, the pattern for tenor clef’s key signature with sharps is different, it goes: up a fifth, then down a fourth, (and repeat).

Why isn’t the tenor clef’s (simpler) sharps pattern used for the other clefs?

  1. For bass clef this pattern would put the first sharp (F♯) below the staff, which is not aesthetically pleasing.
  2. Tradition.
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  • I don't agree that key signatures are 'recognised', as much as how many #/b are there?. (except by constant use). Doubt if anyone actually looks at any key signature and works out which notes are # or b! Simply the number of them should be enough. I used to read music where the composer wrote, say in key A, 3# any old where. We all knew where they were supposed to be - where else could they be?! And often use fingers to denote keys - no lines or spaces to bother with then!
    – Tim
    Dec 28, 2023 at 9:26
  • @Tim For example, when I see four flats (in the conventional places) I instantly think “that’s A-flat major / F minor”. I don’t think “B-flat, E-flat, A-flat, D-flat”, and don’t have to count them “one, two, three, four” either. Any key signature that I don’t recognise and I think “Why? Bartók why?” Dec 28, 2023 at 10:16
  • With you all the way with Bartok. Tried and failed! But just about any other music, yes, 4b would indicate to most musos Ab/Fm. But instinctively we see the key sig. and translate it. When it gets to more than 5#, I need to 1) think about it, or 2) fiddle with the key change on the electric keyboard!, or 3)abort...
    – Tim
    Dec 28, 2023 at 11:03
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It's just the convention to list the flats by ascending fourths then descending fifths.

To underscore the point about conventions, and to show those conventions can change, look at this old edition of Couperin...

enter image description here

...the flats are not all staggered and they are repeated at the octave.

You could be unconventional and put the G flat in the higher octave, and people would understand it's a key signature of 6 flats.

My point is it isn't written in stone, nor purely logical, it's a convention.

https://imslp.org/wiki/Pi%C3%A8ces_de_clavecin%2C_Livre_1_(Couperin%2C_Fran%C3%A7ois)

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  • Paper becomes cheaper, as the modern arrangement takes more space? Just speculating :-). I wonder whether notation software such as Sibelius and Finale accommodate this ... Dec 29, 2023 at 22:41
  • Even the time signature is upside-down. Dec 29, 2023 at 22:46

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