I see, (perhaps we jump a fractal or two away with this?) the # 693 with the 9 as the pinnacle of the pyramid... don't ask me why... it'd take too long I think... vortex math? the enneagram? something sufi-ish? I honestly don't even know. someone tell me please... Ha!
oh yes, the 432 frequency is harmonic/healing. we could reference soffegio (parden my spelling?) frequencies &| isochronic tones &| brainwave synchronization, but also easily see the digital root of 9, then to the 6 via 4x3x2(=24, or 6), and the midpoint/pillar as the 3 already... also it's fractal and oscillating nature of course...
but i had to update just now, because i'm hoping that i haven't used the wrong terminology, nor implied this particular to be the one best ... because i don't know... here's a tad more of what i do know/think though:
1) Main concert tuning of instruments centuries ago may have been 432 Hz ... now it's 440 Hz. i see the fractality in the prior (432), so i like it, and i see control yet also powerful combined stability perhaps (and then the 0 i always see as beautiful for some reason) in the latter (440 Hz). if you're still reading, you might enjoy my stuff on numerology &| gematria. oh, i also see the 7 in the # 440. do you see it? i'm happy to show you if not, just comment/msg/email me if curious. (damn, i was speaking to a friend that labels himself as having asperger's or something [i think he's just connected well mentally/spiritually, and perhaps more so than myself] and in discussion it was mentioned how "curiosity killed the cat" but he then mentioned/asked "do you know what resurrected the cat...?" my only quick response/guess was the 9 lives thing, and that it was simply #2 or #3's turn/phase, but his was funny and along the lines of "the awe of the journey and resulting satisfaction of finding the answer."
2) Over 150 Gregorian chants, way back when, used to (perhaps? maybe? more research needed...) use a 6 tone scale, the low pole being 392 Hz and the high being 852 Hz. Most know inherently (along with other #s of course) the correspondences of the #6, but for those that don't remember, well I see sex (as in French? "sex" is a prefix for the #6, as in sexlet being a group of 6 musicians.) I also see the cube as it is turned with a vertex pointing properly at me as a (in 2d) hexagon. I also see creation in this #. I want to say in vortex math it is the one side that oscillates from the 3 and back, both controlled by the 9?
3) There is a very popular 5 tone scale used in jazz/blues & other types of improvisational musix called the pentatonic of course which spans 1 octave (say C to 1 octave higher C) and contains 5 different notes all spaced evenly with 1 whole step between.
I should research a bit more on other #s involved in different scales/modes/etc, then will post these certain frequencies here.