Viola tuner

Viola strings: notes and Hz

Equal temperament. The viola's A string is the A above middle C, the same 440 Hz as a violin's A and an A440 tuning fork. The reference switch above moves every string.

How to tune a viola with this tuner

Tap Start tuning and allow the microphone, then tap A and bow the open A string with a long, even stroke. The needle shows the cents above or below A4; when the string holds within five cents for a moment, it ticks. Then tap D, G and C and do the same; bow a string that is still to tune and close to its own note and the tuner switches to it by itself after three readings. When all four have ticked, tap Start tuning and go over them once more, C to A: each string you tune changes the pressure on the bridge a little and nudges the others. With the microphone off, a tap on a string plays its note, and on a viola all four sound at their real pitch, even on a phone speaker, so you can tune by ear against them too.

The C is the string to watch. It is thick and slow: after a peg turn it keeps creeping for a minute as the string settles over the bridge and the nut, so if it is far off, bring it roughly up to pitch before you start; then tune A, D, G and C, and check the C again at the end. If the needle jumps, rest left-hand fingers lightly on the strings you aren't tuning so they don't ring along. Bowed, it reads steadier than plucked. If your section tunes to 442 Hz, switch the reference before you start and every string follows.

Viola tuning next to the violin and the cello

A viola is tuned a fifth below the violin: it drops the violin's E and adds a C underneath, so its G, D and A are the violin's three lower strings, note for note. The cello has the same four letters an octave lower. A violin string set will not do on a viola, though: the strings are made for its longer string length. Viola music is written in alto clef, where the middle line is middle C (C4), the C an octave above your open C string. For the neighbours: the violin tuner and the cello tuner.

Pegs, fine tuners and which way to turn

Most violas have a fine tuner on the A string, often a steel A; beginners' violas have one on every string. Fine tuners are for the last few cents: one turned clockwise, screwed in, raises the pitch, counterclockwise lowers it, and a quarter turn is a few cents; when one runs out of thread, back it off to the middle and take the change on the peg. The C and G pegs sit on the left of the pegbox as you face the viola, the D and A pegs on the right. On a normally strung viola, turning the top of the peg toward the scroll raises the pitch. Turn a peg in small steps while you press it into the pegbox, so it holds, and approach the note from below: overshoot, go back under, come up again. If a peg slips back, the wood has shrunk in dry air; if it jumps and creaks, it is sticking. Peg compound helps both; with none at hand, rub soft pencil graphite on the shiny bands of a sticking peg. A peg that slips even with compound needs refitting at a luthier's.

How to tune a viola by ear

1. Take the A from an A440 tuning fork, a piano's A above middle C, or a tap on the A string above with the microphone off. On a viola it is the same note as the open string, with no octave to jump. Strike the fork on your knee and touch its stem to the top of the bridge: the viola sounds the A loud enough to tune against with both hands free.
2. Bow A and D together and turn the D until the fifth stops beating and rings open.
3. Then D with G, then G with C.

The low fifth is the hard one, and there is a reason. A fifth beats where the third harmonic of the lower string meets the second of the upper one. With a string 5 cents off, the A and D fifth beats about 2.5 times a second; the C and G fifth, lower down, only about once a second. Hold the C and G longer and listen to the slow swell, not for a fast wobble.

Pure fifths against the needle

Fifths tuned until they stop beating are pure, 701.96 cents, almost 2 cents wider than the tuner's equal temperament. From an A at 440, pure fifths put the D at 293.33 Hz, the G at 195.56 and the C at 130.37, 5.9 cents under the tuner's 130.81. So a viola tuned well by ear shows its C about 6 cents low, and the C won't tick. In a quartet that is often what you want. Next to a piano, keep the fifths a little narrow, so your C meets the piano's.

Viola sizes

Violas are measured by the length of the body in inches, not in fractions like violins: full-size violas run from about 15 to 17 inches, and smaller players start on 12 to 14 inches. Every size is tuned C G D A. The string length changes with the size, so buy strings marked for yours: a set for a 16-inch viola is too long and too slack on a 14-inch one.

Why a viola goes out of tune

• New strings stretch for several days; synthetic strings settle faster than gut, steel fastest.
• Weather. Heating season dries the wood and the pegs slip; a humid summer makes them stick.
• The bridge. Tuning up drags the top of the bridge toward the fingerboard. Glance at it from the side every few tunings: it should stand straight up from the top. A leaning bridge can warp or fall, and the sound post inside can fall with it.
• How often. Every time you take it out, and again after travel or a change of weather.
• Strings off. Change one string at a time, never all four, so the bridge and the sound post stay where the luthier set them.

A clip-on tuner on the bridge reads the wood's vibration and ignores a noisy room; on a phone this page reads the air, so bow toward the microphone and keep the room quiet.

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