Many thanks, mainterm, for looking into my thoughts on tempo regarding my rendition of Sor's Opus 60 #8. In conclusion, you, Jess Phillips and also Yisrael Van Handel (at least initiallymainterm wrote: ↑Thu Dec 27, 2018 8:47 pm...
Well - I certainly didn't mean to imply a judgement regarding your choice of tempo, rather to learn your thoughts on it. And to this end I appreciate your thorough response.
As for my opinion - were I to perform this piece before an audience, my musical instincts take me toward a slower tempo than you are using. I simply prefer to "sing" this piece more slowly - and as the melody is the same in the variation, I would keep the tempo the same for both as you reason above.
AND
Objective rules for Sor's tempos: this information - if it exists - is unknown to me. There's some scholarship on it, there's speculation, there's a fair bit of opinion, but objective criteria? No.
I suspect that if one wanted to embark on a music theory / notation research and analysis project you could do quite a lot with just the scores we have of Sor's music - I'm not aware of any such effort - at least not to the extent that a PhD dissertation in theory or analysis would require. Perhaps its out there, maybe someone here knows of such an effort...?
I've spent a fair bit of time reading about tempo in 19th century western art music and it's a rabbit hole. A really interesting rabbit hole, but not one that yields generic rules such as: Andante = <insert absolute/objective thing here>.

As for articles on Fernando Sor, I only read one far, dealing with his apparent use of the musical rest as a polysemous sign, written by Ricardo Iván Barceló Abeijón, an Iberian-Uruguayan guitarist, teacher, and composer who attended the Real Conservatorio Superior de Música, Madrid, and earned his PhD in music at Aveiro University in Portugal. Interesting...