Bass tuner

Standard bass tuning: E A D G in Hz

At A4 = 440 Hz, equal temperament. A four-string bass is an octave below a guitar's four lowest strings. The reference switch above moves every string to 432 or 442 Hz.

How to tune a bass guitar with this tuner

Tap Start tuning and allow the microphone. The tuner asks for the E string first: pluck it once, let it ring, and the needle shows how many cents it sits above or below E1. Too low, tighten the string; too high, loosen it; a quarter turn of the key, then pluck again. Which way tightens depends on the headstock, so the first quarter turn tells you. When the string stays within five cents for a moment it ticks, and the tuner asks for A, then D, then G. Pluck a different string that is still to tune and close to its own note, and the tuner switches to it after three readings; to recheck a string already ticked, tap its note. When all four have ticked, tap Start tuning again and go round once more: raising one string's tension bends the neck a hair and lowers the others, so the second pass is usually a few cents of touch-up. Drop D and 5-string are the switches above the strings. With the microphone off, a tap on a string plays its note; a phone speaker plays it an octave up, because it can't play the real one.

Many phone microphones roll off below about 100 Hz, and a bass lives between 41 and 98 Hz (the five-string's low B at 31). So the tuner reads the overtones: the octave above a string vibrates twice as fast (on a stiff bass string a hair more, well under a few cents), so it is almost as exact, and a reading an octave off still lands on the right string. Hold the phone within an arm's length, pluck firmly with the side of a finger over the end of the neck (a hard pluck reads a few cents sharp for its first instant, so read the needle once the note has settled, not on the attack), and rest your fretting hand on the other strings. If the needle wanders on the low E, play the harmonic at the 12th fret instead: E2, one octave up, a cleaner tone. A bass through an amp works too: put the phone by the speaker, not on it.

Every bass tuning in Hz: drop D, 5-string, 6-string, drop C and lower

The switches hold standard, drop D and five-string. For B standard on four strings, pick 5-string and tune to its first four notes, B E A D. A six-string is the five-string plus a high C3: tune it to the 5th fret of the G string, or use the high-C switch of the 5-string bass tuner. For E♭ standard, D standard and the lower drop tunings, the pitch detector names any note with its cents, down to B0 (30.9 Hz); each tap reads three seconds. Drop A's A0 is below that: tune the low string until its 12th-fret harmonic matches the open A string, A1.

Drop D, drop C and what the strings say about it

Each has its own page with the tuner set to it: bass drop D, bass drop C and bass half step down.

Drop D lowers only the E string, a whole step, to D1. Check it two ways: the 7th fret of the dropped string is A1, the open A string, and its 12th-fret harmonic is D2, the open D string. A string's tension goes with the square of its pitch, so drop D leaves the low string with 21 % less tension, drop C 37 % less and drop B 44 % less. On a standard 45–105 set, drop D plays fine and drop C is loose but playable. For drop B or A, fit a heavier low string (a five-string set's B is around .125 to .135) and expect the nut slot to need widening and the neck relief a look, or the string buzzes and won't hold its pitch.

How to tune a bass without a tuner

1. Get one E1 from somewhere: the lowest E on a piano, a keyboard, or a tap on the E string above with the microphone off.
2. Press the E string at the 5th fret: that is A1. Tune the open A string until the two sound as one.
3. The 5th fret of the A string gives D2 for the D string, the 5th fret of the D string gives G2 for the G string.

Harmonics are cleaner than fretted notes: the harmonic over the 5th fret of one string and over the 7th fret of the next string up are the same pitch, E3 for the E and A strings. Play both, and the slow wobble between them stops when the strings agree. One catch a tuner shows at once: harmonics make pure fourths, each 2 cents narrower than the tuner's equal temperament, so tuned all the way up from E by harmonics, the G ends about 6 cents flat. Tune by harmonics, then check the G against the needle.

In tune open, out of tune up the neck: intonation

If every open string ticks but chords at the 12th fret sound sour, the problem is intonation, the length of each string set by its saddle. Tune the open string until it ticks. The tuner then moves on, so tap that string's note above to bring it back (after the last string it stops: tap Start tuning, then the string). Play the note fretted at the 12th fret: the tuner folds octaves, so the needle shows how far it sits from the open string's octave. Fretted note sharp: move that saddle back, away from the neck. Flat: move it forward. Retune the open string after each move and check again, with fresh strings, in the tuning you play.

Why a bass goes out of tune, and how often to tune

• New strings stretch. Tune, lift each string a little away from the fretboard along its length, retune, and repeat until it stops dropping. A new set settles within a day or two of playing.
• Temperature. A bass carried from a cold car into a warm room drifts as the neck and strings warm up. Tune after ten minutes in the room, not at the door.
• Humidity. Dry winter heating and a damp summer move the neck, and the tuning with it. Kept in its case at roughly 40–50 % humidity and room temperature, a bass drifts least.
• Tune up to the note. If a string is sharp, go below the note and come back up, so the gear holds against the string's pull.
• How often. Every time you pick it up, and on a gig every few songs. A bass usually holds its tuning longer than a guitar.

Phone, clip-on or pedal tuner

A phone is fine at home and in lessons. A clip-on tuner reads vibrations through the headstock, so a loud room doesn't bother it; a pedal tuner reads the cable and is the steadiest on stage, and most mute the signal while you tune. All three show the same thing this page does: the note and how far off it is. For an upright, the double bass tuner has its orchestral and solo tunings; for a guitar, the guitar tuner.

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