There's not a chart with that designation in the OP's initial post. I re-scanned the first couple pages and the links provided, and I see that referenced but not in use on a contemporary chart.
I've never said, You're wrong. All I'm saying is I can't recall seeing that on a chart in practical application.
Should I post a home-made chart with this voicing? Will that validate it? TL5, if you basing your position on what you "can't recall seeing that on a chart in practical application", this is an incomplete experience. Once again, your examples have holes in them - they are inconsistent and not well noted.
Attempt?
Yes, it indicates the bass note. The horizontal line may not fit your idea of perfection, but it's quite commonly displayed that way in the real world. I can produce numerous examples of professionally published lead sheets and rhythm scores with the bass movement marked in that fashion. Maybe you're the one who needs to get out more (referencing you're earlier insult).
(PM me for links of examples or for the full score of any previous samples.)
"Slash" chords are simply the noted chord with an indication of the desired bass. These are a more
modern versions of Figured Bass - since MOST people can't read Roman Numerals with inferiors plus having to know what key they are in.
Poly-chords are noted with the use of a "Horizontal" line - common (and correct) method. The "Horizontal" line indicates that there are TWO independent chords to be sounded simultaneously And guess what? Either or both of those chords could ALSO have a "Slash" to indicate, further, an inversion or bass note.
I can only explain how I'd approach it.
I think it was quite intentional, because the practical application is exactly as I stated earlier.
Gb2 would have Gb, Ab, and Db. The arranger specifically wanted the third (Bb) in the bass for the ascending line, but not in the instruments playing the upper harmony (guitar, piano, synth?).
Of course that could have been written as Gbadd2, but that would put the Bb in the upper harmony instruments and it would have failed to specify a Bb as the bass guitar note. Neither of which the arranger wanted.
So then, we know from this example, that the pitch 'Ab' absolutely cannot be sound as the highest voice? Why not call this
"pro" charted chord a Gbadd2/Bb then?
It's hard to ascertain what the composer/copyist (from your 2nd and 3rd examples) wants since some of the chords are noted as poly-chords. Yes, that's REALLY the way Poly-chords are written.
added: Since it's nearly impossible with a QWERTY keyboard to create a Poly-Chord with the "Horizontal" line, some use this:
|
So... Here is a C triad over a D triad Poly-Chord:
C | D
As I stated, you can also incorporate the "Slash" into a Poly-Chord:
A/B | Cm -- low to high: C, Eb, G | B, A, C#, E
The so-called "Pro" charts that I've read, that were typeset or done by hand by a copyist, used a "Horizontal" line.
I've been going through a bunch of charts looking for examples of either one of these notations. Ironically, I didn't find an example of either
Maybe none of these chords really exist!