Does the voicing of a chord affect the name it's been given? If not, what does?

Question

So I came across a YouTube video where the guy kept referring to a chord as Cm♭6 (C minor flat 6th). However, it seems to me that with a little rearranging this could also be written as a simple major seventh chord (G♯M7).

Is it because of the particular voicing that he's using (C E♭ G G♯) that he refers to it as Cm♭6? Or is there some other "rule" on naming chords at play here?

Here's the link to the video I was talking about: Video Link

He discusses this particular chord around 01:06 in the video.

Answer 1

The voicing doesn't usually affect what a chord gets named, although there are slash chords which tell what the chord is, and what note is the lowest - its inversion.

If he's calling it Cm♭6, then it won't be spelled with a G♯. G♯ is an augmented 5th. The ♭6 of C is A♭. As soon as I hear stuff like that that's inaccurate, I question everything that's being said.

So, with the notes C, E♭, G and A♭, that would normally be known as A♭ major 7. More specifically, A♭maj7/C.

The voicings of major 7 chords rarely have a root note and the major 7th note next to each other - it causes beating, as their pitches are only a semitone apart.

There are several chords with more than one name - C6 and Am7 come to mind. Both contain C E G A. Usually, the lowest note (either C or A) will determine what it's called, but context can be important too.

I'm sceptical that the chord you ask about is actually Cm♭6.

Answer 2

I don't know the video, but normally one uses only 1 instance of each letter. Also (with exceptions), the best guess at a chord comes from considering the notes as stacked thirds. This would give A♭-C-E♭-G as the chord. This an A♭ major seventh. (The same as the OP G# major seventh.) (A G♯ major seventh would be G♯-B♯-D♯-F♯♯, not as easy to write though.)

Also, chord names are not all that important; chord usage is. (The names are useful as a shorthand though.)

Whether this chord should be written as an A♭ major seventh or some sort of G sixth depends on the context. If the next (and preceding) chords seem to be based on G or C or D then a chord rooted on G is best. If they connect as a D♭ or A♭ or E♭ chord, an A♭ is best.

I prefer just to use ordinary staff notation as that is generally easier to read. (The melody and chords and bass can easily be separated at sight.)

Answer 3

I disagree that Ab/C is a useful way to label the first chord, at least in the context of Laura Palmer's theme. It completely obscures the modal flavour of the composition. Someone above described it as being in either C Aeolian or C Phrygian - in my interpretation, it is unambiguously in C Aeolian.

C - D - Eb - F - G - Ab - Bb

There is in fact space for a G in the chord, in my opinion, depending on how it is voiced. So Abmaj7/C is technically more accurate than Ab/C, but again this is not how the chord functions in its relationship to the rest of the phrase.

Cminb6 - Cm - Cm7 - Cm - Cminb6 - Cm - Cm - Cm

...is how I would label each chord from bar to bar. Or I suppose you could simply indicate that the notes Ab and Bb are floating in and out over a Cm pedal.

To anyone else who claims that the chord could be described as an Abmaj7, and uses the excuse that they "don't know the context"...I can only respond with: Exactly. You are ignoring the context.

Incidentally, Signals Music Studio is not a YouTube channel that's in the habit of dumbing down music theory for its audience. Although he has an accessible and non-threatening approach to his lessons, he has a firm grasp of the content and he doesn't often get it wrong.

Answer 4

Context is key! The video is a guitar lesson where the presenter is demonstrating some open campfire voicings that give a spooky effect. In the clip highlighted by the OP, he's showing the basic E minor open voicing, but with the open-b moved up to the c on the first fret. He calls this E minor b6 and demonstrates how to use it to play "Laura Palmer's Theme" from twin peaks.

The OP was insightful enough to recognize that this group of notes is identical to an inverted major 7 chord, so clearly, there is some ambiguity here. So why might we call this Eminb6?

First off, there are two main uses for writing chord symbols: One is to guide a player in improvising a melody or providing an improvised accompaniment to a melody. Two would be to help describe what's going on in a particular piece of music, but it's important to understand that the symbols are always approximate, the music may include, embellishments, passing tones and color tones (or even passing chords) that may or may not be implied by the chord symbol at all. In Laura Palmer's theme (as played in this video), an e-minor chord is held while the notes C and D are alternated over it. This is basically atmospheric mood music that evokes the Aeolian mode. E is pretty clearly the root note. As such e-minor-flat 6 is a pretty good description when you're isolating the part where C is in the melody.

However, you probably won't ever see minb6 written on a chord sheet meant for improvisers. As used in the video, this is a very "modal" sound, either Aeolian or Phrygian, which wasn't something used much in the early tin pan ally songs that chord notation originally arose to describe. In modern Jazz, there's no accepted standard way to evoke Aeolian or Phrygian mode sounds, but one of the common alternatives would be to use slash chords (Cmaj7/E or Cmaj#11/E). I think the video presenter chose to call the chord Eminb6 because the video was not targeted at jazz musicians or academic music theorist, but beginner to intermediate level guitarists, and the voicing being used was derived from the Emin open voicing that beginner guitarists learn.

Answer 5

Some people insist that chord symbols tell us nothing about voicing or inversion (with the exception of 'slash bass' notation).

However, in practice, it can be useful to distinguish between C6 and Am7. And (to be a little more controversial - this one tends to arouse the haters :-) between C(add2) and C(add 9). So, although Cm♭6 (note that's got the ♭6 as WELL as the 5th) is certainly the same notes as A♭maj7, it's conceivably useful to be able to write it in both ways.

Answer 6

EDIT:

Your question and the linked video really seem like two different issues. You asked about voicings but the guitar lesson video issue is more about identifying a bona fide chord.

I think the guitar lesson video is transcribing the music incorrectly. The video's transcription - roughly tones ^5 b^6 ^5 ^1 b^7 ^1 over a complete, root position minor triad - sounds wrong when compared to the actual soundtrack.

From listening to the soundtrack, the first change sounds like root movement by third. That is a so-called weak progression with a characteristic feel. Importantly the voice leading uses an inversion on the first chord.

I think this transcription in Cm is correct...

The chord symbols Ab/C Cm Cm7 Cm seem OK. Notice the symbol is a first inversion Ab major triad. It's a simple triad not a seventh chord. It isn't Cmb6 (that's how the guitar lesson would label it) because there isn't a fifth (G) present. That is what I think the guitar lesson video overlooks.

You might think: Ab/C or Cmb6, six of one, half dozen of another. But that is being indifferent to inversions and what is a bona fide chord. It's bad harmony.

To me the essence of the harmony is Ab/C Cm or in Roman numerals Cm: VI6/3 i. It plays with the ambiguous feeling between major and minor. Importantly C is the tonic and in this style either a plain Cm triad or a Cm7 could server as a tonic chord. Functionally it doesn't seem to make much difference and so the Bb tone isn't very important in the functional sense.

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Original answer about chord symbols, inversions, and enharmonic spellings:

My understanding is when jazz chord symbols are used the harmony is root position unless indicated otherwise with "slash" notation to denote what tone is in the bass.

https://en.wikipedia.org/wiki/Chord_names_and_symbols_(popular_music)#Inversions

With that understanding about inversions chords like C6 and Am7 should not be considered the same thing. Both are assumed to be in root position so the former has a C in the bass and the latter an A in the bass.

If you indicate the inversion, then you could get genuinely redundant symbols like...

C6/A = Am7 or C6 = Am7/C

Regardless, the symbols don't tell you about close or open voicing.

The only way I know to indicate specific voicing is with "drop" voicing. From a close position chord various voices get dropped (inverted down an octave) and then you get a voicing with specific intervals. So a drop 2 G7 is voiced D (P4) G (M3) B (d5) F.

I'm pretty sure I have seen lead sheets with a written note for a drop voicing.

...he's using (C E♭ G G♯) that he refers to it as Cm♭6?

It's hard to talk about this stuff when enharmonics are handled indifferently!

Cm♭6 would be C Eb G Ab

Cm(add♯5) would be C E♭ G G♯ the 'add' being necessary to indicate a perfect fifth and an augmented fifth are both present.

G♯M7 would be G♯ B♯ D♯ Fx

Cm♭6/A♭ would be Ab C Eb G but could be more simply labelled AbM7 depending on what is the actual root and both are enharmonically equal to G♯M7. Those symbols provide inversion info, so you know what tone is in the bass, but the symbols don't really tell the specific voicing (specific intervals between all the tones.)