Q4: What distinguishes the large-hole shakuhachi from a flute with regular-sized holes?
A: The large-hole shakuhachi is an innovation of master player and flutemaker John Kaizan Neptune. The idea involved here is that since sound emerges from the tone holes as well as from the open end of the shakuhachi, enlarging these holes reduces impedance (or resistance of air flow) resulting in a somewhat "bigger" sound. To compensate for pitch, which would be raised in this process, the tone holes are lowered, made oval and oriented to the direction of the fingers to facilitate closure.
The large-hole shakuhachi is an anomaly and not widely used in Japan. I do not recommend this model flute for beginners, players purchasing their first instrument or students buying a shakuhachi for use in study with a traditional teacher. Fingering may be a bit more difficult to master and the subtle distinctions in tonality tend to be lost on the novice. It is an excellent instrument for experienced shakuhachi players wishing to explore a greater depth of tonality.