>where he explored some (to me) weird tunings, starting with one where A = 432Hz
That's just changing a convention, not a tuning in the sense talked elsewhere in this thread (how we divide notes), but "what our starting frequency is".
A=432 and A=440 is just as arbitrary. They just had to pick something so they would all match.
The main difference is that 432 is associated with a set of new age, healing, "universe", etc. BS claims in certain "spiritual" circles...
Some late baroque-period harpsichords had a selectable A: you could chose ~430, ~410, or ~390. The adjustment came from sliding the keyboards to the left or right based on which A you wanted. Supposedly A = 390 or even lower was used by the French in the renaissance, so you wanted your harpsichord to be able to accurately play historical music.
Tuning your orchestra high was sort of the 19th century equivalent of the modern loudness war. The problem is that orchestras tuning to ever higher pitches meant that singers had to sing higher to match, and it was putting serious strain on their voices, which can easily lead to injuries.
Having some sort of agreement setting a standard was just something of an "enough is enough" sort of moment. It just amuses me to no end that this was achieved by writing it into the Treaty of Versailles, of all things. We're settling a freaking world war, so let's make sure we settle the issue of orchestra pitch as part of the treaty.
Though it is true that a lot of older string instruments weren't designed to take the tension of modern strings at modern pitch, and some of them really open up at a slightly lower pitch. I'm building lyres, and many lyre people are from that "A432 resonates with the universe" crowd, so I've been using it — and I can't deny that there seems to be a sweet spot in sound for a lot of instruments at that pitch. I honestly have wondered if there's some physiological reason so many people prefer it.
Aside from the universe, there's a very practical point related to this, which is that the instrument has other resonances besides those of the strings. E.g. I have read that the frames of harpsichords are tuned to particular resonances, which is part of what gives different keys different qualities.
Well he does go into Pythagorean tuning later in the video[1], both a proper one and one which was made to "look nice", so bit more to it than that from what I understood.
Or I might be wrong, I know nothing about music[2].
That's just changing a convention, not a tuning in the sense talked elsewhere in this thread (how we divide notes), but "what our starting frequency is".
A=432 and A=440 is just as arbitrary. They just had to pick something so they would all match.
The main difference is that 432 is associated with a set of new age, healing, "universe", etc. BS claims in certain "spiritual" circles...