I was reading this book and on the "Circle of Fifths" chapter, it claims that keys with sharp key signatures (C, G, D, ...) are "often thought by musicians" to be "bright" sounding, whereas those with flat key signatures (F, Bb, Eb, ...) sound "darker".

In our equal temperament scales (which I believe to be the ones the author is talking about here), how would this make any sense? Is C not an arbitrarily chosen frequency? If C is an arbitrary point in the frequency space, and equal temperament scales have the same distance between each semitone, it makes no sense for different keys to have different colors based on their relationship to C.

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    On their own, without modulation as in leftaroundabout's answer, I find C# minor and F# minor to be fairly dark-sounding. Commented Apr 2, 2016 at 16:21
  • We're not in a world of equal temperament. Not even on keyboards if you mean "perfectly equal". Keyboard tuners use "stretching" and master tuners use other non-equal-temperament techniques as well.
    – Jeff Y
    Commented Oct 18, 2019 at 14:11
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    @JeffY but stretching is not analogous to the unequal temperaments used in earlier centuries. The stretching does not give different intervals to different keys; it just compensates for the inharmonicity of the stiff strings.
    – phoog
    Commented Apr 22, 2021 at 20:47
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    Perhaps the book is wrong. Sometime people inject opinion in their description of things without scientific fact,
    – user50691
    Commented Apr 23, 2021 at 20:04

11 Answers 11


It certainly holds some truth, irrespective of tuning system, in the following sense: modulating to a key with more sharps evokes a “bright” sensation; modulating to more flat evokes a “dark” sensation. This is somewhat tangible: raising accidentals are likely to be perceived as “uplifting”.
(Except when they're not; perception is of course highly subjective and often culturally influenced.)
Now, a key with many sharps is more likely to have been reached by modulation from a flatter key, than from one with even more sharps. In this sense, a key with sharps is statistically more likely to appear bright.

Whether this has any relevance to pop music is doubtful. Pop doesn't tend to modulate much at all, except for the last repetition of the chorus... almost always up, although if you raise the entire key by a half-tone it may well be notated with five flats instead of the seven sharps you'd need.

Other thoughts: different keys are differently well-suited for various instruments.

  • Violins prefer sharp keys somewhat. Viola and celli prefer sharps too, though not as much a violins do – the strings are one step down the circle of fifths. Double bass has no preference for either sharps or flats, I think.
  • Among oboists and flutist, everybody seems to have different feelings about whether sharp or flat keys are nicer to play.
  • Trumpets and trombones have some preference for keys with a few flats.
  • Saxophones, B♭ clarinets, horns and tubas have a strong preference for flats.

Of course this too can't be more than a rule of thumb, but there does appear to be some trend that brighter instruments are more comfortable with sharper keys. This may also contribute to a perception that compositions / passages in flat keys sound darker: because they feature dark instruments more prominently!

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    So modulating from E up a semitone to F would not be uplifting? Or would we then be in the key of E#?! Talking specific instruments, guitars sound brighter in E, but tune them down a semitone from standard, and funnily enough, they sound bright in Eb!
    – Tim
    Commented Apr 2, 2016 at 15:59
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    I guess you're 'blessed' with absolute pitch? E modulating to F is not uncommon.
    – Tim
    Commented Apr 2, 2016 at 16:23
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    Trumpets and trombones do have a preference for flat keys, because they are most usually built in Bb. This is not true of the modern flute, which is centered around C, and the oboe is actually easier to play in G major and D major (no forked fingerings) than in any flat key. Commented Apr 2, 2016 at 17:33
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    On a piano the sharp keys have the third of the scale on a black note and the others on either a white or a black note, which will at best emphasise the third and at worst equalise it. In flat keys up to Db the opposite holds so the third will tend to be de-emphasised.
    – user207421
    Commented Apr 3, 2016 at 5:48
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    @EJP - it's an interesting point, but as a piano player for 60 yrs, I would have noticed that in my playing. As it is, I'm pretty sure any imbalance between notes played in a triad should have been ironed out by now. Other players may have this phenomenon, but I find it doubtful. But even if it rings true, it would only work for touch sensitive chordal instruments such as piano. How could the idea transfer to, say, guitar?
    – Tim
    Commented Apr 4, 2016 at 6:43

It may have made a subtle difference in the days before ET but since then, F# = Gb, for example, so how can two identical sounding keys portray different emotions, or indeed sound different? I'm guessing that before ET F# and Gb did sound slightly different, and possibly playing them back to back could give a perception of 'bright and dark'.

Having said that, some people have very heightened senses, and certain keys/tunings, or in particular, chords, will evoke another sense for them. As in - a dominant 7th makes them think 'green', or even 'vanilla flavoured', so 'bright and dark' fits in well with that concept. But certainly not as a general rule. The 'bright/dark' is another theory that isn't a rule or law. Opinion, not fact.

  • This is what I thought. However, my question wasn't geared towards a F# vs Gb situation. The claim in the book is that scales with sharp key sigs such as C, G, D are bright, while flat key sigs such as F, Bb, Eb are dark. I will clarify on the original question.
    – diegovb
    Commented Apr 2, 2016 at 9:20
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    Fair comment. However, when we get to keys like F# (with 6#) and Gb (with 6b), the same applies. Can the writer distinguish between those two, as an example?
    – Tim
    Commented Apr 2, 2016 at 9:29

If ...

  • we're talking in an equal temperament context, and
  • There aren't any other tuning oddities (stretch tuning, etc.) and
  • we're assuming a relative sense of hearing (no absolute sense of pitch or key)

...then pretty much by definition, there's no fundamental, general distinction that can be drawn between flat keys and sharp keys. After all, if we go round the circle of fifths, the relative movement between F major (one flat) and A♭ major (four flats) is the same as moving between A♭ major (four flats) and B major (five sharps).

So, for what genuine reasons might musicians often think otherwise?

  • We might not only be talking about an equal temperament context after all; This collective "musicians experience" might include wisdom passed down from the pre-equal temperament era. Speculating for a moment, it might even be that pre-equal temperament tunings influenced the repertoire written during those times, with the result that "darker-sounding" pieces were written in what were then darker-sounding keys; those keys are not darker-sounding now (in equal temperament), but the correlation might remain...

  • Some musicians may have a sense of "relative key", recognising C major/A minor as a 'home' key and hearing other keys as relative to that. (I'm pretty sure I don't hear this way, but then I don't have perfect pitch either, and many musicians do). Even if this were the case though, you'd imagine that hearing C as a 'home' key would be somewhat arbitrary (though it could make sense for pianists).

  • On some instruments, even those that are nominally tuned in equal temperament, there are real reasons why different keys might sound different : the pitches of open strings; the resonances of the instrument; imperfect tempering, and so on. On guitar, for example, the sharp keys G, D, A, and E are commonly used. However, that is an accident of the tuning of the instrument.

However, these are all 'special cases'; none of these reasons suggest a general distinction that can be drawn between flat keys and sharp keys.


No, at least with not with twelve-tone equal temperament (https://en.wikipedia.org/wiki/Equal_temperament). I.e. with Piano Music, you will not hear a difference.

However with some instruments and vocal music, one cannot assume perfect twelve-tone pitch. Nevertheless I highly doubt, that a listener could tell apart F major (one "flat") from E# major ("sharp" scale).

Sharp and flat scales are more of a product of our western music notation system that centers around C Major or A Minor being the default and then notating half-tone "corrections" for other scales.

  • There's not much perfect about 12-edo tuning, in fact I call it an effective but dirty compromise. Not only vocals, but also most string and wind instruments will naturally deviate from it towards just intonation; in principle that works the same way for all keys, so like with 12-edo you don't have any “particular sound of a key”. Though at least with string instruments, some keys may have empty strings which can't be freely intonated (but some styles avoid empty strings altogether anyway). Commented Apr 2, 2016 at 15:15
  • @leftaroundabout I think you mean "open" strings -- that is, not stopped with a finger but left to vibrate along their entire length.
    – phoog
    Commented Jun 24, 2019 at 21:52
  • @phoog yes. The German term is Leersaiten, which would literally translate to “empty strings”. Never noticed it wasn't called this in English. Commented Jun 24, 2019 at 22:01

I agree, that makes no sense. It's all relative.

If keys have "flavors", it's only because of (lack of) familiarity borne of our tendency to play in only a handful of keys.

Keys may be all the same, relative, to our ear, but certainly not to the way they lay on a fingerboard.

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    Yep. I know several pianists who prefer very flat or very sharp keys because they involve less sticking your fingers between the black keys. That's also presumably why the children's piano piece "Peter Peter Pumpkin Eater" is played only on the black keys. Commented Apr 3, 2016 at 8:18
  • Of course, key preference differs by instrument, so I guess my statement 'handful of keys' presupposes a particular instrument. I'm a guitar player, so I had a completely different thing in mind than avoiding black or white keys... And horn players would have other driving factors... Still, it would be interesting to catalog the keys of a wide variety of music, both popular and classic.
    – joe
    Commented Apr 3, 2016 at 16:53
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    @ScottWallace - the reason is more likely that it's a pentatonic tune, and the 5 black keys are easy for kids to play on.
    – Tim
    Commented Apr 4, 2016 at 6:48
  • @ScottWallace - just listened to it, and it isn't pentatonic, so cannot be played only on the black keys.
    – Tim
    Commented Apr 4, 2016 at 6:59
  • @Tim- The version I learned as a kid is pentatonic, with only the notes F#, G#, A#, C#, and D#. Commented Apr 5, 2016 at 9:50

I think keys (notes) in isolation don't matter. Intervals do. If your song is played on mostly black keys with occasional whites (where needed), and your friend's song is played on mostly white keys with occasional blacks, the two can express the same mood. Absolute pitch does not affect the type of emotions invoked, the sequence of tones and semi-tones (intervals) does. I think that is what a raga in Indian classical music is about. That is what a scale in western music is also about. Given that a raga also has a grammar (of allowed and forbidden sequences of notes) to follow, it is more sure to invoke a particular mood. A western composition would achieve this effect through the 'art'of the composer. Despite the association (or affinity) of major scales with bright and minor scales with sombre moods, a composer can reverse this effect through his 'art'.


In my education, the circle of fifths/fourths works clockwise adding sharps and goes a full 360 degrees adding sharps all the way around until you arrive back at the beginning. The same holds true moving in a counterclockwise direction, but adding flats instead of sharps. That means a sharp key is also interpreted in theory as a flat key, and a flat key may be interpreted as a sharp key. So for me, I find such a statement to be unnecessarily confusing. I just accept that each key has it's own characteristics, which I need to know, and I try to avoid such generalizations as bright and dark according to sharp or flat since each individual key can theoretically be classified sharp or flat.

  • This certainly applies in the world of equal temperament. If you go from C major to the key a tritone away, have you gone to F# major or Gb major? There's no way to tell!
    – phoog
    Commented Jun 24, 2019 at 21:50

As a wind band and sometimes orchestral composer and arranger, there are a few practical things to think about that are corollary to the bright/dark debate. The key itself is of little consequence due to equal and just temperament, but the physics of wind and string instruments do make subtle differences.

In a group setting, unfretted strings (in tune) will sound brighter than the same notes stopped with a finger due to the micro-tuning of each individual. The wider pitch band created by stopping sounds darker than a true unison. Some orchestras (I know Boston SO used to do this) purposefully tune their sections slightly out of tune (+/- 1 cent) to mitigate the difference between open and stopped strings.

Woodwinds generally have darker sounds the more holes that are covered; this isn't so dependent on key as on tessitura.

Brass instruments tend to get a darker sound with more valves opened. Keys that have more unvalved partials are heard as brighter, the more valves in combination are darker.

Generally, wind and string players work to reduce the differences in timbre and pitch our instruments create, but small differences do still exist.


It's been my observation that the "mood" in music can indeed be conveyed by whether it is in a flat or sharp key. Remember, this is a very subjective matter, and others' perceptions may differ. That being said...

It's in print somewhere

I remember reading in a music encyclopedia/dictionary about 25 years ago (a thick but single-volume book, certainly not the New Grove!) in which it also claimed that

flat keys generally sound "dark"


sharp keys generally sound "bright"

(I also remember the same book stating that major keys are generally "happy" and minor keys "sad"--an opinion certainly corroborated by André Previn.)

Traversing the circle of fifths

I would also suggest that the "dark" (or "bright") mood implied by the author is intensified by adding more flats (or sharps). But only to a certain point. For example,

  • C major: Neutral or ordinary mood
  • F major ➔ B♭ ➔ E♭ ➔ A♭: Increasing solemness or "darkness" in mood
  • G major ➔ D ➔ A ➔ E: Increasing "brightness" in mood

These moods seem to "max out" at 4♭ or 4♯ - my personal opinion is that A♭ major sounds preponderantly solemn or dark whereas E major is about as bright and cheery one can get in music. A lot of Phil Collins' songs are in flat keys (especially A♭ major), and Sheryl Crow seems to have an affinity for sharp keys (especially E major).

The mood conveyed by 5♭/7♯, 6♭/6♯, or 7♭/5♯ is sort of a "no-man's land" - the mood is neither "dark" or "bright" but perhaps mysterious, dreamy, or blissful. I might also suggest that since this region on the circle of fifths is antipodal to C major, then it naturally goes that these keys are anything but "ordinary". As an example, Gustav Mahler exploited the "mysteriousness" of G♭ major for the choral entry in his "Resurrection" Symphony:

Langsam. Misterioso (Fig. 31)

Putting the cart before the horse

I often wonder if the causal effect is reversed; i.e. an abundance of "bright"-sounding or "dark"-sounding songs have been written before the tonality of the song was decided. It's more as if the mood was established in the lyrics and melody before the composer put them to music. Just an alternate "devil's advocate" theory...


I have perfect pitch, so often I find myself hearing a song for the first time and already knowing what key in which it's played. This also has the side effect of me trying to determine the mood the composer was in when he/she wrote the song--i.e. "this is a 'happy' song so I'll write it in D major" or "this is a really sad song so it'll be in F minor", etc.


There are a number of reasons why this effect is sometimes observed.

Often, musicians and audiences will notice that modulations in the sharp direction (adding sharps = raising notes) often feel as though the key has been "lifted", as some notes are higher. In pop songs that modulate up a half-step (or even a whole step), often the same brightness effect is undeniable. If keys get too sharp, they may be perceived as flat, due to enharmonic properties.

Even when there is no context to compare the key to, often musicians will conceptualise sharp keys as brighter than flat ones, since they 1) know the key and 2) know that this key is often modulated to by adding sharps. Whether this is apparent in their interpretation of the music is unknown.

Listeners with perfect pitch will know what the key is in their heads, and even if they aren't musicians, they may be able to recognise that one song seems to be in a bright key compared to another. This may be similar to synesthesia, and synesthetes, of course, would perceive some keys as being brighter than others (but which ones can vary considerably).

Historically, composers would name their pieces after the key they were written in (Canon in D, etc.). This is a vestige of a time before equal temperament, when different keys really did sound different because the intervals were not equal. And of course, the whole "D minor is the saddest key" thing.

In music where equal temperament is not used, different keys could be brighter than others.

Finally, possibly, composers subconsciously compose music differently in sharp keys than bright ones. They might often be perceived as brighter if composers compose more brightly in sharp keys, whatever that could mean.

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    So did you say (a long time ago) that if a song mods from E (4#) up to F (1b) that it sounds brighter? That means one flat could be brighter than four sharps; opposite to the OP's thoughts?
    – Tim
    Commented Feb 15, 2019 at 11:07
  • But F is enharmonic to E♯ (8♯), adding seven sharps! (I like to explain the half-step brightness in terms of adding seven sharps, and similarly whole step up being two sharps) This example works a lot better with C major moving to C♯ major and the like, but the important part is that effectively seven sharps or an enharmonic equivalent gets added to the key signature.
    – user45266
    Commented Feb 19, 2019 at 19:56
  • I understand what you're saying! How about going from F# to G? Don't tell me it's really going from 6# to 9#..!
    – Tim
    Commented Feb 20, 2019 at 8:25
  • Well, it's really 6♯ to 13♯ (F♯♯), in my explanation. Or the same but 6♭ to 1♯. Yes, musically it's pure nonsense, but it makes sense auditorily, since it's enharmonic. Another way to justify the 7 sharps is that all seven notes get raised a half step.
    – user45266
    Commented Feb 20, 2019 at 15:56


But to the extent that lowering pitches has a "darkening" mood and raising a "brightening" mood, then modulating in the direction of keys with flats - technically modulating by descending fifth, which can be done with naturals too - has a "darkening" effect.

Of course you can use all sort of adjectives. You could call it "mellower" or something like that. It's all pretty subjective.

But, one thing that is not so subjective is the idea of denouement and the narrative arc. It's a literary term for the part of a story that comes after the climax where dramatic tensions are resolved. The objective part is about form and the logic is pretty simple. If dramatic tension rises until a climax, then what follows is a resolving of tension in a denouement. The denouement leads to the conclusion.

Classical sonata form follows a similar "narrative" arc with structural dissonance. The modulation to the dominant creates a "structural" dissonance leading to a dramatic climax in the development section, and the recapitulation returns things to the opening key to "resolve" the structural tension. The recapitulation is analogous to a denouement. It is common to have some kind of statement in the key of the subdominant in the recapitulation. The subdominant is of course a move in the direction of "flat keys", modulation by descending fifth. So, "flat keys" do have a association with lowering of intensity - "darkening" if you put it in terms of brightness - as felt by their denouement effect in a recapitulation.

One of the important takeaways from this is the relative relationship of keys. It is not key signatures with flats are dark. It's the relative change of lower pitches by modulating by descending fifths (in the direction of key signatures with flats on the circle of fifths) that creates a "darkening" mood. So much of musical expression works of such relative relationships and changes. Rarely is one isolated element expressive. Music is a temporal art.

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