Re: So, what?
Reply #3 –
Caveat: I'm not formally trained in music theory, what I know I've "soaked up through my skin", so the following is what I've learned that way and may not accurately equate to "the rules".
If there is a 1/4 = 1/4 at each time signature change then the tempo remains at 1/4 = 168. If there is no marking at the first 2/4 and/or the 3/2 then I would expect the 1/4 = 1/4 to be implicit.
The most likely reason for the time sig. changes is to adjust the meter so that implied emphasis appears in the right place.
3/4 = 1, 2, 3 1, 2, 3 1, 2, 3
2/4 = 1, 2 1, 2 1, 2 1, 2
3/2 = a "wider" 1, 2, 3; or perhaps 1, 2, 3, 4, 5, 6; or maybe 1, 2, 3, 4, 5, 6. This will depend on context though the latter 2 possibilities would most likely have been notated as 6/4 rather than 3/2.
It's also possible the 3/2 could be interpreted as 1/4 = 1/2 (which would halve double the original tempo), thus the explicit 1/4 = 1/4 at the following 2/4 (which would keep the half double original tempo) - let context be your guide...
I've played in a lot of bands and orchestras under a lot of different conductors and and band leaders and the one constant is that none of them seem to agree on how changes from x/4 to x/2 to x/8 should relate... They almost always use context to figure it out.
Pretty sure most composers have their own ideas too.
I'm not sure what Gould has to say about this but I'm confident her interpretation is most likely correct. Tempo equations help a LOT
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