What is this chord?

[A-board]

C#°

I've never seen the "°" in a chord notation. I found it in a version of Georgia on My Mind. Straight c# doesn't fit.

Thanks in advance,

[AlanN]

C# diminished. Flat the 3, the 5, add a 6, you're there.

[Tom C]

What's cool about the diminished chord pattern is, you can moved it anywhere as long as any one of the notes you are playing is a c#. It does not matter which one.

[Jon Hall]

C# diminished 7th. Root - flatted 3rd - flatted 5th - double flatted 7th

[EdHanrahan]

What I find a bit frustrating:

When fretted players call for a "diminished" chord, they invariably mean the "diminished 7th". Doesn't necessarily work that way in keyboard circles. (In the key of C -for simplicity-, "pure" Bdim is B,D,F). I've asked for clarification on occasion and gotten back a "Well what else IS there?" sort of reaction.

What I find a lot of fun:

... you can moved it anywhere as long as any one of the notes you are playing is a c#. It does not matter which one.

Which means that the pattern repeats every 3rd fret as you go up the neck. A jazzy move is to slide up 3 frets on each beat of a measure - hey, you'll sound like Les Paul! Off the top of my head, the only example I can cite is the Beatles' version of "Till There Was You". Not sure if George H. played it that way, but Tom S. in my college rock band sure did!

And for those of us, uhmm, "mature" enough to remember, it was played-to-death by the live studio guitarists on early TV game shows. Also by the pianists in pre-talkie B&W movies, usually as Nellie Mae was being tied to the RR tracks!

[Toni Schula]

C#°
Looks to me like a programming language somebody developed in a fever

[journeybear]

Hold on just a sec. I've always thought a diminished chord was formed by the notes of the root and the tones up two successive minor intervals (up three frets, up another three frets), also seen as flatting the V tone on a minor chord. Now you're telling me to also add the tone another minor third up?

This made me want to crawl back into bed, pull the covers over my head, and go back to sleep, hoping the nightmare would be over when I woke up.

I went to the wiki to see what their experts had to say, and there are two entries (naturally): one for diminished seventh chord, one for diminished triad. The first page is devoted to what you guys are talking about: 1, b3, b5, 6; the second page is devoted to what I'm talking about: 1, b3, b5. It also contains the following disambiguation attempt:

In some sheet music books[citation needed], Cdim or C° denotes a diminished seventh chord (a four note chord) with root C, and Cm-5 or Cm♭5 denotes a diminished triad with root C. However, in some modern jazz books and some music theory literature[citation needed], Cdim or C° denotes a diminished triad, while Cdim7 or C°7 denotes a diminished seventh chord.

I am including the "[citation needed]" notes, because that could mean whoever contributed this bit isn't really knowledgeable. Or it could mean he knows what he knows but can't back it up, or simply hasn't backed it up. The problem I'm having here (besides being stunned to learn I may have been operating under a misapprehension for a very long time) is that a designation could exist which implies a seventh tone (sixth, really) without saying so in the notation. That is, for example, the designations for C#7, C#m7, C#ma7, and so on, specify the "7" in the chord name. The example cited by the OP does not include a "7", so I'm inclined to believe it isn't called for.

The red flag for me was what Tom C said. This is true for a C#°7, as you guys have it, but not for a C#°, as I see it. That statement is also true for augmented chords, comprised of root and two successive major thirds (root, up four frets, up four frets, also seen as sharping the V tone in a major chord), but that's another matter.

Help!

[ombudsman]

Long story short, altered chords and those that were popularized in jazz are less consistent in their naming compared to the more familiar and basic diatonic chords. It's not like there is some authority or governing body on this.

You have to go by the context of the musical style and what you know or can see about the notation style of whomever wrote the chart. In a bebop jazz chart I assume diminished chords have sevenths, in a pop song I assume they don't, unless I have other information available.

This isn't really that unusual of a task. In classical notation there are likewise sometimes stylistic elements that are not specified on the page but need to be understood and respected by the performer by drawing on their training and knowledge of the style, composer, and piece, usually having to do with rhythm or with what is possible on a given instrument.

[EdHanrahan]

I feel your pain, JB!

Here's an interesting (hopefully not too frustrating!) observation that I've made since working thru "Piano For Dummies" in the past year or two. I'll keep this in the key of C for simplicity:

It strikes me that the "pure" 7-based chord in the key of C, being B-diminished (B,D,F), contains 3 of the 4 notes in C's "dominant 7th" chord, being G7. (Ya know, the chord that 96.713% of the time forces you to go back to the tonic C chord?) Bdim, in fact, lacks only G7s root, and it's sort of clear that, again in context, your head usually "hears" the root note whether it's actually there or not.

As a result, and only when heard in the context of the preceding music, the Bdim can often, if not usually/generally/always, be substituted for that dominant G7 chord, because it sound so much like it in context.

Okay folks, get ready to shoot this next comment so full of holes that it looks like Swiss cheese...

My best guess, maybe to make me & JB feel better, is that, in popular usage as opposed to classical, the diminished 7th (yes it is double-flatted) is so often implied because the pure "non-7th-ed" diminished chord is sort of extraneous - it sounds in context just like the dominant 7th chord. (Again, that would be G7 in the key of C).

Of course, YMMV!!!

[ombudsman]

Okay folks, get ready to shoot this next comment so full of holes that it looks like Swiss cheese...

My best guess, maybe to make me & JB feel better, is that, in popular usage as opposed to classical, the diminished 7th (yes it is double-flatted) is so often implied because the pure "non-7th-ed" diminished chord is sort of extraneous - it sounds in context just like the dominant 7th chord. (Again, that would be G7 in the key of C).

Ok, I'll shoot...

The vii in diatonic major as a cousin if not outright sub of the V7 is very much context dependent. You're extrapolating generalizations from what is true about the simplest diatonic chords to songs in general.There are usages of half diminished chords (ie the shape of the vii with it's seventh) and the diminished triad that don't sound or function like a V7, not least because they are not based on a vii root and therefore do not have those notes in common with the V7.

[Bruce Clausen]

Chords aren't really made by taking a major chord and then altering notes. They result from scales. In the key of C, the natural chord on D is minor, on F is major, on B is diminished. These are the chords you get by using the regular scale notes-- no notes have been altered.

The diminished seventh chord is formed on a minor scale (the so-called harmonic minor, since it supplies the key's harmony). In A minor, the natural chord on G# has the notes G#-B-D-F. All normal ("diatonic") scale notes-- nothing altered, let alone "double-flatted".

(And yes, context and function are important and variable.)

[Jim Broyles]

The confusion can partially stem from the fact that the vii° chord of a major scale is a diminished triad, but the extension of adding the diatonic 7th makes it a m7b5 chord, which is known in the biz as a half-diminished chord. In the key of C, this would translate to B D F A - but notice that the A is only the b7 of B. A Bdim7 chord has an Ab there. When you see a chord symbol C#°, the best bet is that the arranger wants a dim7 there. If you play a C#m7b5 it may clash with the melody.

[Jim Broyles]

Chords aren't really made by taking a major chord and then altering notes. They result from scales. In the key of C, the natural chord on D is minor, on F is major, on B is diminished. These are the chords you get by using the regular scale notes-- no notes have been altered.

The diminished seventh chord is formed on a minor scale (the so-called harmonic minor, since it supplies the key's harmony). In A minor, the natural chord on G# has the notes G#-B-D-F. All normal ("diatonic") scale notes-- nothing altered, let alone "double-flatted".

I disagree. Every chord is named by using the major scale of the root and altering notes. If you see Bbm7b5#9, you start with a Bb major scale and flat the 3rd to make it minor; add the b7 because without the designation of "maj" a seventh always refers to the flatted seventh; flat the 5 and sharp the 9. Bb Db Fb Ab C#. Of course the m3 and #9 are the same enharmonic note, so it's how you voice it, and this chord would probably never be used in an arrangement. Still, that's how you arrive at the notes in a chord.

[Pete Martin]

In Jazz theory, "diminished" implies a 4 note chord 1 b3 b5 bb7. In Classical theory, "diminished" implies a 3 note chord 1 b3 b5 and "diminished 7th" is the 4 note type.

I think a lot of stuff in Jazz theory has evolved to make reading charts easier on the fly. It is easier to read the half diminished symbol (the circle with a slash) than all the symbols "m7b5".

[Bruce Clausen]

Every chord is named by using the major scale of the root and altering notes.

Very misleading idea. The chord G#dim7 has nothing at all to do with the scale of G#major (a scale with 8 sharps!)-- it is a diatonic chord in the key of A minor (no sharps). Much simpler to think of the chords in the context of the keys in which they occur.

[Jim Broyles]

Very misleading idea. The chord G#dim7 has nothing at all to do with the scale of G#major (a scale with 8 sharps!)-- it is a diatonic chord in the key of A minor (no sharps). Much simpler to think of the chords in the context of the keys in which they occur.

On the contrary, since individual chords occur in multiple keys I believe it to be much simpler to know one scale and alter notes. I agree that a G#dim7 has nothing to do with a G# major scale, but if you still use the G# major scale to determine the notes in the chord you will always be able to come up with the notes. I'll pretty much guarantee you that every G#dim7 that has ever appeared in an arrangement was not in the key of A minor. In 40 plus years of learning and discussing music theory I have never heard of any other way to name the notes in a chord except by starting with the root's major scale and altering notes according to what the chord symbol says.

BTW, I'd be interested in how a G#dim7 is diatonic to A minor. The diminished triad in the A natural minor scale is B, but the diatonic 7th would be Bm7b5. I get that there is a G# leading tone in the dominant chord (E7) of A minor, but strictly speaking, the G in an Am scale is natural, is it not?

[Bruce Clausen]

Let me see if I can bridge the gap here a little, Jim. The system of chord names used (mainly) by guitarists uses a certain vocabulary to identify chord colours. Major 7, dominant seven, minor seven, and so on. These different colours result from different combinations of intervals: for example a dominant seventh chord has a major third, a perfect fifth, and a minor seventh, counting from its root. In the chord G7, all these notes are diatonic if we're in C major. But if we're in F, that major third is now an altered note, a B natural that disturbs the prevailing F major landscape. (For example, the third bar of Girl from Ipanema.) So a chord can be diatonic in some keys, chromatic in others.

Now let's say I'm playing in A minor, improvising over a G#dim7 chord. If I play an F, I'm playing a chord note that is completely at home in the key of A minor. But if I think of that note F using the method you've presented, I have to tell myself to play a double-flatted F double-sharp!

Simpler I think if we recognize the *intervals* of the chord without reference to a notional major scale. So that "dim7" means a series of three minor third intervals, and only that. Diatonic as the VII chord in minor keys, but very commonly used in other situations, where one or more of its notes is chromatic.

By the way, the figured bass system for writing harmony is much older than the pop shorthand we're discussing here. It is still very widely taught to classical music students. The pop names mean nothing to most of those musicians.

Sorry for taking this discussion probably much farther than the OP intended!

[Jim Broyles]

Okay. Still disagree, and you didn't tell me how G#dim7 is diatonic to Am.
And this:

Now let's say I'm playing in A minor, improvising over a G#dim7 chord. If I play an F, I'm playing a chord note that is completely at home in the key of A minor. But if I think of that note F using the method you've presented, I have to tell myself to play a double-flatted F double-sharp!

makes zero sense to me. Why do you have to tell yourself anything just because you played an F note over a G#dim7? Play the F and call it an F. I'm just telling you how to name the notes in a chord, not how to improvise. Frankly, if I have to think that much during improvisation, it probably sounds horrible. Besides that, in the G#major scale, you would be playing an E#, not an F. If I were you, I'd still call it an F. Nobody says you have to put your improvisation in the key of the root of the chord you are soloing over, only that to name the notes in the chord you start with the root's major scale. This is correct, no matter how many times someone says it isn't.

[UsuallyPickin]

People , I just want to say thank you to the gathering here. I'm a theory minimalist but have always found the demented chords , or as G.H. called them "The naughty chords" tuneful in the right place and the arpeggio fun to slip into a break now and again. This kind of discussion with explanations is what keep me coming back to the Café and the Classifieds which keep my wish list current. Thanks People , R/

[journeybear]

Yikes! Glad I skedaddled when I did. It sure got thick in here real quick.

Jim - I understand how you go about building chords, but I don't think you have to drag the whole scale based on the root into it. A G# whatever is going to be comprised of the tones required for that particular chord, regardles of the scale invilved. And if you're using the chord in a song, which is most likely going to be in a different key than thwt chord anyway, I don't see the point of using the scale corresponding to thst chord's root note. The song the OP wqs asking about isn't in C#, for example, but that chord fits the melody at that moment. There are accidentals involved. On purpose, of course.

Bruce - Saying G# has eight sharps had my head spinning. My experience has led me to believe the maximum number of sharps or flats is six, and then you've gone around the circle and gotten back to none, that is, C. If I go along with you, then what I think you mean is a scale like this: G# A# C C# D# F G G#. I think you want to see this as G# A# B# C# D# E# F## G#. To that, I say nuts! And this is why that's not a G# scale at all, but an Ab scale, with four flats. Just easier to notate that way. And still a bitch to play on a mandolin, either way.

I wonder if A-board is still on board, after all this.

[Laurence Firth]

I agree with Bruce - the method he describes is correct theory and to my thinking easiest. Jim's method is commonly used but always seemed convoluted to me. For example I had a teacher who liked Jim's method and would describe a simple minor chord (the ii chord) this way: root flattened third and a fifth. That's true if you are thinking major sale and altering it. But that's not how the chord is derived. It's derived form the second interval, the forth and the 6th (minor 3rd + major third). I find it easier to think in the key / scale the piece is in and it's scale intervals rather than a major scale starting on the second interval with altered notes. But whatever works for you is what works for you.

[Bertram Henze]

Just an observation from a theory sceptic/antiseptic of many years' standing:

Chord notation was invented as shorthand code for the most common standard triads, where using the code is easier than quoting all the intervals. The more modifications you apply to those triads, the more complicated and unreadable the code becomes, and it would be better and shorter to just quote the intervals instead. Counting half steps above the base note, the diminished chord would be 0-3-6, and any weird chord can never look more complicated than, say, an emergency telephone number (try playing 0-9-11, e.g. C-A-B). We could lose all these Stargate hieroglyphs with that.

[AlanN]

Funny, it's not the first time a thread about this dissonant chord has generated a small amount of (ahem) discord. I know the dim chord is used in countless jazz vibes, everything from bebop to tin pan alley to Django; in grass, I'm trying to come up with tunes that use it and can only think of one: Blue Mule, off Muleskinner. The tune is in B chord, I think the dim is G#dim7. I'd need the mando in hand to say for sure.

Any others?

[Jim Broyles]

Whatever works, of course, but I was taught in my Theory and Harmony class in 1968 this way to name the notes of a chord, and every forum I have ever participated in and every discussion until now has done it this way. Isn't doesn't matter whether journeybear sees the sense of it or not. And you don't get it anyway. I'm saying that you name the notes of a chord by starting with the major scale of the root of the chord you are trying to name. If you see Dm7#5b9 on a chart, the way you name the notes in that chord is by altering the notes of a D major scale. Google it. it is undeniable.

Alan, songs and tunes are in keys, not chords. "B chord" is a chord, not a key.

[AlanN]

hmmm...seems I've heard this before. And seems I've said this before...around here with the pickers I pick with, we say "This one's in B chord...". You, Jim, likely, don't say that. No big deal, in my mind.

How about it...other grass tunes with a dim chord?