MOPS Day, uh, 10. I am doing this one on a Sunday, when no-one is on the interwebs, because it’s the prime example of me using the rule ‘I will finish off all the ideas that were in my lost notebook, even if they are not strictly speaking good ideas’.

It starts from a conversation a few years ago about Tallis’ brilliant 40-part motet, Spem in Alium, combined with various discussions about the dullness of the sort of choral bass line where one only sings on one note. And I happened to wonder: if there are 40 vocal parts, is the number of different pitches that they sing at fewer than the number of people? That is to say, if one were to rearrange it so that each person were singing only on one note (assuming the requisite ability to count like robot ninjas that that would need), how many singers would you need? Yes, I realise this spectacularly misses the point of both Spem and choral music in general. The fact that it’s more or less a big troll is why I found it amusing, and wrote it down in the notebook. The answer, in case you were wondering, is somewhere around 33 depending on various editorial decisions.

I was able to partially automate doing this, so it’s slightly less wasted effort than it looks like, honest. It’s a pdf file, so I’ve put it up on fluffhouse here.