Mujitsu and Tairaku's Shakuhachi BBQ

Ryan Sullivan wrote:

In Tanaguchi's notation, there is often times written a chi-meri with a hollow circle to its upper right. Does anyone know what this designates?

The little circle is used in many honkyoku to indicate a note of the same pitch (and often with a different tone color), but using an alternative fingering to achieve it. The case you are referring to is probably in a piece such as Reiho (Yamagoe), where a series of notes is played (such as the 'Chi-Ru-Tsu-Ru' sequence near the beginning of the piece), and alternate fingerings are used for some of the pitches in the series, both to achieve certain pitches/colors and to make the series playable.

For example (from Taniguchi's teaching materials):

     

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