Shakuhachi hole calculator
The standard shakuhachi is 1.8 shaku long, about 54.5 cm, and sounds D4 (293.66 Hz) with every hole closed. It has five holes, four in front and one for the thumb, giving the notes D F G A C and the octave D. The calculator opens on that flute: D4, a 20 mm bore, a 4 mm wall and 11 mm holes, and gives the tube length and the position of every hole measured from the top edge and from the bottom end.
D shakuhachi, 20 mm bore (estimate)
End-blown flute in D4 (293.7 Hz), 20 mm inside, 4 mm wall, 11 mm holes, at 25 °C, A 440 Hz. Tube length 573.5 mm.
| Hole | Note | Diameter (mm) | From embouchure (mm) | From end (mm) |
|---|---|---|---|---|
| 1 | F4 | 11.0 | 456.0 | 117.4 |
| 2 | G4 | 11.0 | 405.9 | 167.6 |
| 3 | A4 | 11.0 | 358.4 | 215.1 |
| 4 | C5 | 11.0 | 294.1 | 279.4 |
| 5 | D5 | 11.0 | 263.3 | 310.1 |
How to use it
- The type is already set to End-blown and the hole pattern to 5 holes, minor pentatonic. Pick the key of your flute under Fundamental note.
- Enter the inside diameter and the wall of your tube. For PVC, measure with calipers; for bamboo, take the average bore.
- Read the length and the table. Holes are numbered from the bottom: hole 1 is closest to the end, hole 5 is the thumb hole on the back.
- Drill every hole smaller than shown, play, check with the tuner and open each one up gradually, starting with hole 1.
Help and explanations
Everything here is an estimate. The shakuhachi's blowing edge and its bore, which is rarely a straight cylinder, change the pitch, so cut long and tune on the real tube.
How the estimate is made
The calculator treats the shakuhachi as a tube open at both ends and uses the hole equations of Arthur Benade as implemented in Pete Kosel's Flutomat. The bottom end gets the standard open-end correction; the top end, where you blow, is treated as partly closed by the player's face, as in Joe Wolfe and John Smith's acoustic measurements of the shakuhachi at UNSW.
With the default D4 settings at 25 °C (77 °F), the tube comes out at 573.5 mm (22.58″), with holes 117.4, 167.6, 215.1, 279.4 and 310.1 mm from the bottom end. That is about 5% longer than a traditional 54.5 cm flute, on purpose: a real shakuhachi's narrowing bore and utaguchi edge make it play shorter than a plain tube, so you trim the end and enlarge the holes until the notes are right.
Other sizes
Each sun (about 3 cm) of length moves the pitch roughly a semitone. Set the fundamental to C♯4 and the same tube comes out 608.5 mm; a 2.4 shaku flute in A3, on a 22 mm bore with 12 mm holes, comes out 769.4 mm, and its holes spread wide enough that the calculator warns about reach. Long flutes often have offset holes, drilled slightly to one side.
Tips
- Hole size moves position: going from 11 to 9 mm holes moves hole 1 about 7 mm up the tube, away from the end, on the D flute.
- Room temperature counts: at 20 °C the same D flute comes out 568.5 mm, 5 mm shorter than at 25 °C.
- Check each note with the shakuhachi tuner, keeping your head still: meri and kari bend the pitch.
Frequently asked questions
How long is a shakuhachi?
The standard 1.8 shakuhachi is about 54.5 cm and plays D4. The calculator's plain-tube estimate for D is 573.5 mm on a 20 mm bore, deliberately long so you can trim it.
Where do the holes go on a shakuhachi?
On the D flute estimate, at 117.4, 167.6, 215.1 and 279.4 mm from the bottom end for the four front holes and 310.1 mm for the thumb hole, with 11 mm holes.
How many holes does a shakuhachi have?
Five on the traditional flute: four in front and one thumb hole at the back. Seven-hole versions add two extra holes for chromatic notes.
Can I make a shakuhachi from PVC?
Yes. Use a tube of about 20 mm inside diameter for D, enter its wall thickness, cut the blowing edge at the top and tune the length and holes by ear and tuner.
What notes do the shakuhachi holes play?
On a D flute: D4 with all holes closed, then F4, G4, A4 and C5 as you open holes 1 to 4, and D5 from the thumb hole in the calculator's pattern.
How big should the holes be?
The calculator starts at 55% of the bore, 11 mm on 20 mm. Smaller holes sit closer to the top and give a darker sound; drill small and enlarge.