The length from the mouthpiece to the first hole of the shinobue for happon-joshi scale songs which have a reference tone is C is almost equal to the length from the edge of the sound generator to the end of C tube recorder (28-29 cm).
Cを基準音とする八本調子唄用篠笛の歌口から第一孔までの長さと、C管リコーダーの発音部エッジから管端までの長さがほぼ等しい(28-29cm)。