Saw u tuner online
The saw u (so u, ซออู้) is the low two-string fiddle of central Thai classical music. Its body is a coconut shell covered with calfskin, the bow hair runs between the strings, and it is played seated with the instrument upright on the left thigh. It has no fingerboard or frets. It partners the saw duang in the khrueang sai and mahori ensembles. The open strings are a fifth apart: the low string (sai thum) is Do and the high string (sai ek) is Sol, the same pitch as the saw duang's thick string.
Saw u open strings
The tuner convention uses A4 = 440 Hz. The 2021 Fine Arts Department values are as reported by a 2023 study, and not every ensemble uses them.
| String | Thai name | Tuner convention | Fine Arts Dept. 2021 |
|---|---|---|---|
| Sai thum (upper peg) | Do | C4 · 261.63 Hz | ≈ 254.2 Hz (C4 −50 cents) |
| Sai ek (lower peg) | Sol | G4 · 392.00 Hz | ≈ 377.8 Hz (G4 −64 cents) |
Lin, Punvaratorn & Wangphanich (2023), Journal of Roi Kaensarn Academi 8(8)
How to use it
- Tap Turn on microphone, allow access and choose Do–Sol or the approximate khlui phiang o option.
- Start with the high string (lower peg) on Sol, as Thai teachers do when tuning to the khlui, then set the low string (upper peg) a fifth lower on Do.
- Bow one open string at a time with long, light strokes; tilt the bow so the hair touches only that string, and keep your fingers off the strings.
- Turn the peg slowly while pressing it gently into the neck, approach the note from below, then alternate both strings to hear a clean fifth.
Help and explanations
With a Western tuner, the Thai syllables are read as letters (do = C), so this page starts at C4–G4, which is a convention. No source states the octave, but C4–G4 is close to the Thai Fine Arts Department standard (do ≈ 254.2 Hz, sol ≈ 377.8 Hz) and to the range measured in a saw u recording. If your group tunes to a khlui phiang o, choose the approximate B♭3–F4 option and finish by ear.
Do–Sol: Thai pitch and the tuner
The Thai music terminology encyclopedia published by NECTEC explains that the upper peg holds the low string, called sai thum, and the lower peg holds the high string, sai ek. The saw u's sai ek matches the saw duang's sai thum, and its sai thum is five steps lower. Teaching texts tune the sai ek to Sol and the sai thum to Do against the khlui phiang o.
The 2021 Fine Arts Department pitch announcement, as reported by a 2023 study, puts do at about 254.2 Hz and sol at about 377.8 Hz: roughly 50 cents below C4 and 64 cents below G4. If your teacher uses this standard, lock the string and aim the needle at that offset. The same study found that schools do not all follow it; the ranat ek instruments it measured had do anywhere from about 254 to 314 Hz.
The khlui approximation and instrument care
The do of the khlui phiang o, with all holes closed, compares with a piano B♭. In ensembles tuned to that flute, the saw u sits around B♭3–F4. That is an approximation, not a standard, because Thai scale steps don't match twelve semitones. Get close with the tuner, then match the khlui, jakhe or saw duang of your group by ear.
Before tuning, check the rat ok, the cord loop that ties the strings to the neck and acts as the nut, and the bridge on the skin. If the loop slips, both strings change pitch. Calfskin reacts to humidity and new strings stretch, so retune often. The coconut body boosts the overtones of the low string: if the tuner shows C5 or G while you bow Do, bow more lightly and evenly.
Tips
- Don't use the saw duang's Sol–Re on a saw u. The saw u is a fifth lower: Do–Sol.
- Don't look for Do an octave lower (C3, about 130.8 Hz); the strings go slack and the tone becomes weak and unsteady.
- If the sound crackles or hisses, rosin the bow. A steady tone helps the tuner read.
Frequently asked questions
What notes is a saw u tuned to?
Low string Do, high string Sol, a fifth apart. By the tuner convention that is C4 (261.63 Hz) and G4 (392 Hz).
Which saw u string should I tune first?
Thai teaching texts tune the high string to Sol against the khlui phiang o first, then the low string to Do. With a tuner either order works, but check the fifth at the end.
How do I tune a saw u to a saw duang?
Tune the saw duang first, set the saw u's high string to the saw duang's thick string (Sol), then set the saw u's low string a fifth lower, on Do.
Is there an official Thai tuning frequency?
A 2021 Fine Arts Department announcement lists do ≈ 254.2 Hz and sol ≈ 377.8 Hz, but many schools and ensembles keep their own pitch. Ask your teacher or band leader which reference they use.