Erhu tuner

Erhu tuning in Hz

The erhu's relatives

Equal temperament. The gaohu and zhonghu are not on this tuner: use the chromatic tuner for them.

How to tune an erhu with this tuner

Set the reference under the needle first: A = 440 Hz on your own or with recordings, A = 442 if your orchestra or teacher tunes there. Tap start and allow the microphone. Bow a long, even note on the inner string, the one nearest you: the tuner asks for D4. The needle and the cents show how far off it is, and a tick comes when it holds within five cents; then it asks for the outer A4. Read the steady middle of the note, not the scratch of the first stroke. If your ensemble gives you an A, tap the A to start there. With the microphone off, a tap on a note plays it, so you can tune by ear.

The bow hair runs between the two strings and never comes off. To sound the inner D, pull the hair toward you with your middle and ring fingers; to sound the outer A, let the bow lean outward, away from you, so the hair rests on the outer string. Turn the pegs for big changes and the fine tuners, if your erhu has them, for the last few cents. Leave the qianjin, the loop of cord around the neck, where it is: it is not for tuning.

A = 440 or 442?

Tune to the A of the people you play with. 440 Hz is the international standard (ISO 16) and right for practice alone, for recordings and for Western instruments. Many Chinese orchestras tune higher, often to 442. The gap is 7.9 cents: small on paper, easy to hear on a long held note next to an instrument that can't move, like a yangqin or a piano. The switch under the needle sets it, and both strings move with it.

Any chromatic tuner works, a violin or guitar app included, because D4 and A4 are ordinary notes; a violin mode works too, since they are a violin's 3rd and 2nd strings. Check two things: that it lets you set A to 442, and that it shows the octave, so a reading an octave off isn't taken for right.

Pegs, fine tuners and the qianjin

Wooden pegs hold by friction: push the peg into its hole as you turn, and come up to the note from below, so the string pulls it tight instead of letting it creep back. Many modern erhus have geared metal pegs that don't slip. Fine tuners are small screw adjusters on the strings for the last few cents.

The qianjin (千斤) is the erhu's nut: it sets where the sounding length of both strings starts. Raise it, toward the pegs, and the sounding length grows: at the same pitch the tension rises with the square of the length, the notes spread further apart under your fingers and the tone gets brighter; lower it and all three go the other way. A common starting point: elbow on the resonator, forearm along the neck, the qianjin where the base of your palm meets your little finger. If every note in first position comes out flat, or every note sharp, however well the open strings are tuned, look at the qianjin, not the pegs. Set it once, with a teacher if you have one, then tune with the pegs only.

Check the fifth by ear

D4 to A4 is a perfect fifth, the same two notes as the middle strings of a violin. Bow the open strings one after the other: a true fifth sounds settled, a wobble means one string has drifted. For a closer check, touch the inner string lightly at a third of its length from the qianjin and the outer one at half its length: both harmonics are A5, about 880 Hz, and should sound alike. The tuner's fifth is 2 cents narrower than a pure one; nobody hears that.

The jianpu names of the open strings

Erhu music is mostly written in jianpu, numbers for the notes of the scale, and the strings stay on D and A in every key: only their numbers change. A piece marked 1=D is played on "1–5 strings": the inner D is 1 (do), the outer A is 5 (sol).

So when a teacher says "5–2 strings", don't retune: the piece is in G.

How to play the erhu: first notes after tuning

Sit, rest the resonator on your left thigh with the neck upright, and hold the bow underhand, the hair between the strings. In first position with 1=D, the inner string gives 1 open (D), 2 with the first finger (E), 3 with the second (F♯) and 4 with the third (G); the outer string gives 5 open (A), then 6 (B), 7 (C♯) and the high 1 (D). There is no fingerboard: the finger presses the string in the air, and how hard you press moves the note as well as where. To check a stopped note, the pitch detector names any note you hold.

Why an erhu drifts

New steel strings settle within a few days; retune often until they do. Erhu strings have been steel since the 1950s; silk came before (Jonathan Stock, Galpin Society Journal, 1993). The python-skin face and the wooden pegs move with the air: dry air loosens pegs, damp air dulls the skin. Keep the erhu in its case, away from heaters and sunny windows, and let it settle in a new room before you tune.

Is the erhu harder than the violin?

The first sounds come faster: two strings, and a bow that can't slip off them. Playing in tune is the long part, as on any instrument without frets, and harder than on a violin in one way: with no fingerboard under the string, finger pressure changes the pitch too.

The notes you tuned go into Brumm as a short melody over a beat.