Does a c11 chord have to span more than one octave?

[oxxyyd]

I'm doing some automatic chord detections from midi tracks. A chord consisting of c, e, g, d, and f in this order is called C11, I understand. Is it still a C11 if the upper notes, d, and f, are lowered an octave, giving a sequence of c, d, e, f and g? Or should it be called something else?

[Googly Smythe]

I entered these notes into Cubase via the score editor, and the info bar reported that both inversions were C9/11.
I wonder how accuarate the chord detection is in Cubase?

DISCLAIMER!
I have no knowledge of music theory. If a chord sounds right I use it.

[Niklashe]

If the root note is still considered to be c it is still a C11 chord. Where you place the notes doesn't really matter.

[JumpingJackFlash]

I'm doing some automatic chord detections from midi tracks. A chord consisting of c, e, g, d, and f in this order is called C11, I understand. Is it still a C11 if the upper notes, d, and f, are lowered an octave, giving a sequence of c, d, e, f and g? Or should it be called something else?

Actually, technically speaking, eleventh chords like this (as with ninths) should contain the (minor) seventh too (though elevenths are not normally added to major chords because of all the dissonance, so C11 would be rare in any case).

Those notes don't really form an obvious chord in the traditional sense of the term, at least not one that can be easily named. If you're into set theory, you could call it set 5-23, but that's probably not going to mean very much in itself.

As with all things like this, much depends on the musical context. It could be for example that one of the notes is functioning as a pedal or some other kind of unessential note (such as a passing or auxiliary note). In isolation, attaching a name to it is rather pointless.

[oxxyyd]

Ahh, sorry, forgot the flatted B. If I add this to the chord/set of notes, will it live to the C11-requirements, even if all notes lie in the same octave?

[Niklashe]

The simple answer is still Yes! It is a C11 chord. In principle it doesn't really matter in which octave you place the notes. And dissonances like the added 11th in a major chord doesn't have to sound too dissonant if it is placed two octaves above the root chord (if they are placed in the same octave).

But JumpingJackFlash has some points to consider. In isolation naming chords is difficult and even more when they become more complex. Is the song made in C major or any other scale that would use the c major chord (Like F major scale)? In different scales you would name the chord differently perhaps, like if the song was written in G minor.

[MadBrain]

Chords depend on 2 things only:
- Which note is on the bottom/bassline
- Which other notes are present? (octave or order of notes doesn't matter)

So in theory the definition of C11 is that it has: (1) C on the bottom, (2) C D E F G Bb.

However, in practice:
- It's not really important for the 5th (G) to be present in 7th+ chords, which brings it down to C D E F Bb
- 11th chords are a special case because the 11th is super dissonant against the major 3rd (F ~ E). In particular, if you put E on a lower octave than F, it will form a minor 9th (1 octave + 1 semitone) which is super hyper dissonant and is generally never allowed in chord voicings. So 99% of the time, the 3rd (E) is dropped out, which means the required notes are only C D F Bb.
- C11 tends to be written as Bb/C (or Gm7/C) most of the time.

[jancivil]

[...] the definition of C11 is that it has: (1) C on the bottom...

We should be clear that the meaning of our nominative C is that we are given the root of the chord, not that it needs to appear @ the bottom of the structure (or need be the bass necessarily).

- 11th chords are a special case because the 11th is super dissonant against the major 3rd (F ~ E). In particular, if you put E on a lower octave than F, it will form a minor 9th (1 octave + 1 semitone) which is super hyper dissonant and is generally never allowed in chord voicings. So 99% of the time, the 3rd (E) is dropped out, which means the required notes are only C D F Bb.

The thing here is that this whole '11th chord' business is a convention found in modern jazz, and appropriated wherever; the convention was always, 'well... basically, here's a ii7 chord with a cherry on top.'. But you're right, 'the 3rd is typically omitted' will make a good truism as well. There is no particular call for it 'on top' of the I major, musically, though. It would be awkward and just kind of a wrong note.

Not sure if "a minor 9th is super hyper dissonant and is generally never allowed" is intended to be true per se or just true as to the major triad add 11 here. Not the first time I've seen that from you in here and addressed it, but the notion of min. 9 as in itself illegal? Well, in the convention where we appropriated these here extensions <b9 over dominant V7> targeted towards minor is pretty normal for example, and as <11 on top of major I> was never anybody's idea really, we should be mindful of 'what is the actual usage or idea' in preference to absolute proscriptions... in a music perhaps freer from a conventional expectation, for instance an F colliding with the E a min. 9th beneath it while C is pedalling down low needn't be such a worry and one may like to convey it as 'C add 11 (or something). So, yes, in a lead sheet 'C11' typically may as well be conveyed 'Bb/C' (I would bet it's never I major, but a ii function); but wait, context: I'm not assuming <pop/jazz> more than I'm assuming <novice gathering vocabulary or just labels randomly for indefinite use> here in a KVR thread...

[MadBrain]

We should be clear that the meaning of our nominative C is that we are given the root of the chord, not that it needs to appear @ the bottom of the structure (or need be the bass necessarily).

Of course, but if the bass is not C then a different symbol should be used - C11/D for instance if the bass plays D.

The thing here is that this whole '11th chord' business is a convention found in modern jazz, and appropriated wherever;

I'm assuming a jazz/pop context since 11th chords are a lot more common in those styles.

the convention was always, 'well... basically, here's a ii7 chord with a cherry on top.'.

ii7??? The uses of 11ths I've heard are:
- Dominant V7 chord (example)
- Suspension leading to V or V7 (example)
- Rather less commonly, root chord (example)

[...]Not sure if "a minor 9th is super hyper dissonant and is generally never allowed" is intended to be true per se or just true as to the major triad add 11 here. Not the first time I've seen that from you in here and addressed it, but the notion of min. 9 as in itself illegal? Well, in the convention where we appropriated these here extensions <b9 over dominant V7> targeted towards minor is pretty normal for example[...]

Ah, right. "No minor 9ths in chord voicings" is just a jazz arranger rule of thumb, and yes it totally does exclude chords that do have a minor 9th in the chord definition itself, such as C7b9, Csus b9 or Calt7(b9), and it also excludes passage notes etc.

[sjm]

I agree with the preceding comments. I would also expect an 11th to include the 7th and 9th as well as the 11th (otherwise I would call it by a different name). At least in theory.

In practice, that's a lot of notes to be playing at once. So for my own purposes and for the purposes of communication, I might call something an 11th chord that doesn't actually contain all those notes. There are simple real world reasons why you won't voice every note in a chord - on a guitar, for example, you are most likely going to have a problem playing every single note simply because you only have 6 strings. Chords played on the piano are be restricted by the player's hand span and by the fact that playing all the notes in the same octave has a tendency to sound like mush.

So I like to view chord names as a shorthand for guiding me and others. It sets up a framework that we all agree on and says something about the complexity of the music. When I play "Wonderwall" by Oasis as a lounge music piece on piano, for example, I like to extend tha A7sus4 at the end of the verse's chord progression with the 11th. But I don't play the 9th; it's A C# E A D E G A (spread over two hands). At most, I'll chuck in a b9 (Bb) as an incidental note. But to make things simple, I call that an A11, 9th or not. It's a lot easier to remember than other alternatives that may be more explicit about the lack of a 9th in what I am playing. For me, the most important thing to remember is that I am extending the chord in the original version with the 11th.

And at some level, that is really what this is about. We give a chord a name so we can identify it, and use it to communicate. It's shorthand for conveying an idea that helps you and other musicians play the piece as intended. So it is important that your chord name imparts the information you want to convey. In a band setting, you are kind of setting out the notes everyone agrees are "possible" in voicing the chord. It doesn't mean everyone has to play all those notes, nor that we need to monitor what the others are playing, and fill in any notes that seem to have been omitted.



Anyway, on the original question...
The order of the notes in a chord may change how you notate it. depending on your preferred convention. F A C might be notated as F, wheras A C F might be notated as F/A. Or not. I personally never bother writing the bass note unless it is fundamental to the piece that the bass instrument plays these notes, or the bass note is not nominally part of the cord, like G/A. Others are much more obsessive about the bass note in guitar chord fingerings, for example, using D/A for a standard D fingering (A D A D F#).

And of course there are chords that are made up of notes that can belong to different chords with different roots. Take A D E/ D E A. Is it an Asus4 or a Dsus2? E G B D = Em7 or G6? This is highly dependent on context, and what the bass is playing normally plays a big role here. So the order of the notes may influence what you interpret as the root note, and by extension the name of the chord.

[oxxyyd]

Thank you all for your comments. Much appreciated.

My plan is to take the participating midi note numbers and do sort of nomalizedNotes = midiNotes % 12 and then do a table lookup based on the resulting number ( a 12 bit long bit field where the bits/note numbers are either set (note is present), or not). This will give me a set of candidates, say C6 and Am7, which I will decide upon depending on the current scale. Needless to say, this will not give an... unambigous chord name, but hopefully a reasonable suggestion. Guess my next task now will be to think up or find an algorithm for picking the best name from the candidates based on the current scale. Or do any of you happen to know about an existing algorithm?

[jancivil]

We should be clear that the meaning of our nominative C is that we are given the root of the chord, not that it needs to appear @ the bottom of the structure (or need be the bass necessarily).

Of course, but if the bass is not C then a different symbol should be used - C11/D for instance if the bass plays D.

I'm simply referring to inversions: if the bass is Eb, youse may like a new name (particularly given the complications herein) but it may also be de facto a C minor.

the convention was always, 'well... basically, here's a ii7 chord with a cherry on top.'.

ii7??? The uses of 11ths I've heard are:
- Dominant V7 chord (example)
- Suspension leading to V or V7 (example)
- Rather less commonly, root chord (example)

We-eell, I stand by that. With V7 as dominant it's mo'less always gwyne be #11; 'sus leading to V7' is ii in essence ("basically here's ...") IE., subdominant; and our tonic 11th in Maiden Voyage is really quartal harmony.
fmr

[...]Not sure if "a minor 9th is super hyper dissonant and is generally never allowed" is intended to be true per se or just true as to the major triad add 11 here. [...] but the notion of min. 9 as in itself illegal? Well, in the convention where we appropriated these here extensions <b9 over dominant V7> targeted towards minor is pretty normal for example[...]

Ah, right. "No minor 9ths in chord voicings" is just a jazz arranger rule of thumb, and yes it totally does exclude chords that do have a minor 9th in the chord definition itself [...], and it also excludes passage notes etc.

[JumpingJackFlash]

...Guess my next task now will be to think up or find an algorithm for picking the best name from the candidates based on the current scale. Or do any of you happen to know about an existing algorithm?

Is this a mathematical project or are you trying to create music?

Music isn't an exact science; algorithms aren't going to mean very much. If you want to analyse music in a meaningful way, you need the experience of doing that. As I said, things depend on context; how it's played etc. On paper, a sonority could be labelled as a certain chord but the aural effect in practice might be very different. - It's like trying to appreciate the Mona Lisa by performing a spectral analysis of the colours used.

Obviously if you're doing this purely for the scientific aspect, that's fine - to each his own. But if you're trying to be a better musician, you'd be far better off with piano lessons or something.

[oxxyyd]

Is this a mathematical project or are you trying to create music?

Neither. It's an attempt to do what cubase does acc to first answer above. Or, to use your analogy, appreciate the level of appreciation of Mona Lisa that can be reached by analysing her midi content from a chord perspective. If she was a set of chords.

[jancivil]

Well, you know, algos at this level are by definition cut-n-dried, so that subtle smile of big ol' Mona won't be so much sussed by it...