I'm working on several of the Messiaen preludes.
In "Chant d'extase dans un paysage triste," there are some square fermatas (in the "un peu plus vif" section).
I don't recall ever seeing a square fermata. What does it mean?
I think it might mean longer than usual... if so, how is that to be interpreted in this case, where the fermata is over an eighth note (r.h.) and a sixteenth note (l.h.), played together. A fermata usually lengthens a long note, not a short note, and a a fermata might mean to stretch the note to double or perhaps triple its length. In this case, does this really mean that the notes should be really stretched out, as if they were, say, a doubled/tripled half-note? Or is the fermata to be understood in the context of an eighth/sixteenth note tempo, so that it amounts to a doubled/tripled eighth/sixteenth note? (I understand that a fermata shouldn't normally be timed. I'm just trying to get the idea across.)
Thanks for any information or suggestions.