Discussion on Observations on the Florid Song
First of all, the chapter from which you cite is on Divisions, meaning groupings of moving notes sung on one vowel. So he is saying that i and u are not as good for runs as the other vowels.
The second part of your question relates to the 2nd and 4th vowels, which are e and o. But he is only talking about their closed versions, and only in the context of DIVISIONS, not in general. So I take this to mean that the closed e and closed o should be opened in running passages and ornaments.
I hope this helps. These old books are definitely worth studying. They are very much about "back to basics" that are not taught enough today.
ohhhhhhhhhhhh... I thought he meant "Divisions" as in breaks in the voice, ie passaggi. Because /i/ and /u/ are vowels that have lower secondi passaggi than the rest, and can be difficult for singers in the 'breaks'.
I actually asked my teacher about this too, and he basically said screw it - maybe in Tosi's day you could modify your vowels to open versions or neighboring vowels, but nowadays people expect closed vowels, especially in German and French singing. Sometimes it's a fight even to get away with modification on the top notes!
I have to figure out a way to get these PDFs onto my iPhone for portable reading...
then we can see why we need forums like this. The advice about divisions is different from sustained singing. Also, Tosti was writing about singing in Italian.
Singers modify vowels to near neighbors all the time. You'll hear it in good singers in all languages.
I had no idea about this, but parts of Tosi's "Observations on the Florid Song" seem kind of nuts to me. On page 56, when he's talking about the Italian vowels (a e i o u), he says "Every master knows, that on the third and fifth vowel the divisions are the worst." This much I get, I definitely have the biggest gear shift into head voice on /i/i and /u/... but then Tosi goes on to say "in the best schools the second and fourth were not permitted, when these two vowels are pronounced close or united."
That's what I don't get - in the best voice schools, you're not allowed to sing "ee" or "oh" at all? Ever? How can you pronounce anything in Italian without those vowels? And what does he mean by "when these two vowels are pronounced close or united?" Does he mean like in words like "addio"? Or is "close" another way to say "closed", as in the quality of the vowel?
Anyone know anything about this?