MJCube wrote:In the case of this guitar excerpt, I notice it is certainly harder for me to read the 32nd-note run at sight without the beam break. In your Bach excerpt mm. 3 and 18 are easy because they’re completely scalar; m. 20 is harder to parse at first, but then it’s a sequence, so the pattern gets ingrained quickly. And the unbroken beam in each bar helps to emphasize the sequence, rather than the beats.
(Also to my eye secondary beam breaks don’t suggest accentuation as much as complete breaks.)
Those are excellent points: some patterns lend themselves better than others to unbroken beaming, and secondary beam breaks are not as disruptive as complete breaks, which is what makes them so useful.
A corollary would be that beaming style can bring out or obscure the meaning of pattern. In the Bach example, the unbroken run of a 12th in the third measure represents an expansion of the opening five-note motive of the piece. Breaking the 16ths into 4 + 4 + 4 would work against this relationship. The beaming also suggests a very fast tempo for this piece and in one beat per measure.

- Bach Partita.jpg (23.31 KiB) Viewed 10598 times
Come to think of it, clarifying secondary beam breaking may be a relatively new notation. I don't recall seeing it in autographs or early editions of Baroque and Classic music, so Bach may have only had a choice between complete breaks or no breaks.
Here is another example, which I may have used before. Not only does Liszt not break primary or secondary beams in this first edition, he doesn't even break at the end of the measure, for a similar reason to the Bach: the pattern represents a long E# that finally resolves to F# at the last minute.

- Liszt beaming.jpg (57.19 KiB) Viewed 10598 times
Here is the Peters edition edited by Emil von Sauer, who adds secondary beam breaks. To me this is needless and disruptive.

- Liszt beaming 2.jpg (43.29 KiB) Viewed 10598 times
Unbroken beaming pervades the entire Hungarian Rhapsody no. 11. Some of the patterns are not simple scales and thus harder to read, as you pointed out.
http://petrucci.mus.auth.gr/imglnks/usi ... 244.11.pdf
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