So there is a clever notation system that a French musician invented that is very popular in Asia. The benefit here is that if one is looking at a piece and wants to see root, three, five, etc., boy does it have you covered. I just learned about it, and was amazed that I was unfamiliar with it (it seems similar to Nashville Numbers, but older). Guitar Pro has support, and apparently some other engraving software as well.
Interesting stuff! Still, itâs a prerequisite that you already have at least some understanding of traditional theory to use this, so if thatâs the case you may as well just learn to read standard notation. But I suppose for speedâs sake, this could be a good system - sort of like âuniversal tablatureâ (except for transposing instruments).
I think itâs useful in conjunction with regular notation, give it a shot if you have a recent version of Guitar Pro (8.1 or later). Iâm still trying to figure out just how to use it, but Iâm glad that they added it (presumably for the Asian market).
Right off the bat this is breaking my brain, because I see that BourrĂ©e as E minor (which it is), but this system is viewing it all as G major. So, whatâs written in the melody as 6 7 1 to start feels to me like it should really be 1 2 3 (in E minor). I donât know if Jianpu typically treats everything as major, though.
Hmm neat idea, but irrelevant if a) you already know how to read well and b) understand theory. Intuitively you know your place (if that makes sense?) intervalically in reference to the key signature and the chords being played over. Kind of an âon the flyâ harmonic and melodic analysis. Might be a good stepping stone for someone without schooling or experience in that sort of thing? Thatâs just me, though - I am nobody, rock on!
Yes, it apparently only treats things as being a major scale. Note how Guitar Pro hinted 6=e instead of saying 1=g. Indeed, I noticed some of their bug fixes that indicated that a previous release mistakenly would have started this off as a 1, instead of as a 6, what I think is correct.
Now, is it âreasonableâ to start with this as being in the key of G? You know better than me. I concluded that sheet music cannot directly expose the mode or intent of the composer, hence itâs OK, and that itâs just one view of many (TAB, numbered musical notation, traditional notation, Nashville numbers, etc.). My concern is this: If they accept a second mode (the minor scale), why not another, and then another, and then, what is the benefit? I concluded that its inventors made the âright decision,â but Iâm really quite ignorant in this area.
Well, in this specific case, the piece both starts (ignoring the pickup measure) and ends with the focus being E: E and a minor third (G) in the beginning, and E plus an octave at the end. There are twists and turns along the way, but E is home. So starting off calling E, the root, 6, is a little odd. But!
This does sort of simplify things if you need to read something with no/little prep. It just removes possibilities, boiling it all down to be as basic as possible. Weird for me, but probably beneficial for someone else.
BUT (again) this results in some very strange things: how do define an E minor triad in G? As 6 1 3? But if youâre in the key of D, now an Emin triad is 2 4 6? And in C it becomes 3 5 7. So the use here is pretty limited only to quicker reading, and not analysis or deeper understanding, as I see it.
Right, alluding to what I said above, it would diminish its value. But I still say its value mainly lies in being able to read something quickly (similar to Nashville numbers).
I think you hit the nail on the head, it seems great for simple transposition from one key to another with no effort, and this is exactly my intended use. I agree with you that a theorist or composer will likely have particular keys in mind, and the â1â will annoy them to no end! What I like is that there is an on/off button in Guitar Pro (itâs right next to the buttons to turn on TAB, etc.).
But while I have you here, I have a question:
1=Ionian, supposedly âhappyâ
3=Phrygian, supposedly âexoticâ
6=Aeolian, supposedly âsadâ
Is it really worthwhile to redefine â1â in each of the modes, or just think of it as one scale, and say, âyah, ends on the 6, so itâs âsadâ or possibly dance music (seriously).â My ears just canât get that out of the music⊠I donât get the âflavorâ of these modes, etc.
My real confusion was hearing the classical guys say things like âF minor has deep depression.â I was saying, âWTF, how is that possible, what is wrong with my ears/brain?â Then, I realized that this was before equally tempered scales, hence it might actually have been true (to those with great ears). Thatâs what Iâd like to see come back, some cats can go into the studio and not have equally tempered tuning but do something like metal in F minor. 
Not just that, but you could use the same sheet of music (if you went pure jianpu with no other notation) for guitar, bass, accordion, xylophone⊠anything that isnât a transposing instrument (like clarinet for example).
Well, I think having two categories, major and minor, is a necessity, and therefore â1â would need to shift. True modal pieces really arenât all that common though, but if I came across something like Lydian, Iâd just keep it as major and throw in an accidental for the augmented fourth.
There is a post here where modal key signatures were discussed, whether it made more sense to write C Lydian as G major, for example, or C and use F# where needed in the music. Getting a little out into the weeds from this topic, but if youâre curious:
I read that, and was really confused. The correct answer seems to be obvious, whatever its composer wrote on the key signature. Thatâs the end of the discussion, right?
Now, letâs say that one played a trick on us and and gave us the exact same notes in all fifteen key signatures, and challenged us, âwhich one is the âbestâ for the music?â This too is obvious, Iâd just count all of the accidentals in the body of the music and minimize that⊠ultimately, the sheet music isnât an analytical tool, itâs for performance, and easy reading? Then again, I might be missing important things here, I know next to zero about this topic!
From the perspective of pure reading, I suppose this is fine.
But what if the notes in the melody are C E B A F# (EDIT: over a C bass note that never changes)? There is the one sharp, F, and the next note that would normally be sharp, C, isnât, so the key of G would be right⊠except there are no G notes to be found at all, and this is really C lydian. So calling it the key of G doesnât work for me, unless we now want to think of all key signatures as X potential mode, which just seems messy. But it boils down to: are you just trying to read this music, or understand it so that perhaps you could improvise over it, or borrow some compositional ideas, or something like that?
Why do we spell âcnidarianâ like that, instead of how it sounds: nydehreeun?
Iâd say that advanced people (composers/improvisers/scholars/etc.) should use whatever notation they want, Iâm unqualified to comment.
But for ordinary readers, it would seem that:
4=C as the hint (vs. 1=G)Does that seem right? 
Yeah, seems right!