How to Tune a Bass Guitar

The four strings, and the fifth

• 4th string: E1, 41.20 Hz.Thickest. One octave below a guitar's low E.
• 3rd string: A1, 55 Hz.
• 2nd string: D2, 73.42 Hz.
• 1st string: G2, 98 Hz. Thinnest.
• Five-string: B0, 30.87 Hz, added below the E. Six-string basses usually add a high C at C3, 130.81 Hz, on top as well.

Every gap is a perfect fourth (five semitones) with no exception anywhere. That regularity is the quiet advantage a bass has over a guitar: there is no odd interval in the middle, so every scale shape and every arpeggio pattern transfers unchanged from string to string, and the fifth-fret tuning method below has no exception in it either.

Why tuners lie about the bottom string

This is the one awkward thing about tuning a bass, and it is worth understanding rather than blaming the tuner.

A tuner works out pitch by measuring how often the waveform repeats. At 41 Hz each repetition takes about 24 milliseconds, and at 31 Hz (a five-string's low B) about 32. To be confident, the tuner needs to observe several cycles, so a low note simply takes longer to measure than a high one. That is why the display wanders for a second before settling.

The second problem is louder. A thick string vibrating at 41 Hz also produces overtones at 82, 123, 164 Hz and upward, and on a bass those overtones are frequently louder than the fundamental, especially on the initial attack, and especially through a bridge pickup. So the tuner hears the loudest thing, decides that is the note, and confidently tells you your low E is an E one or two octaves higher. It is not wrong about the frequency; it is wrong about which frequency you meant.

Three fixes, in order of how often they work:

• Play softer and wait. A gentle pluck near the neck produces a rounder tone with a stronger fundamental. Let the attack pass and read the number that settles.
• Tune the harmonic. Touch the string lightly directly over the 12th fret and pluck. That gives you a nearly pure tone at exactly double the frequency (82.41 Hz for the low E) which any tuner locks onto instantly. The string is in tune when its harmonic is.
• Roll the tone control back. On a passive bass this cuts the high overtones before the signal ever reaches the tuner, leaving the fundamental as the loudest thing in the room.

Tuning it

1. Mute the strings you are not tuning. Rest your palm across them. A tuner hearing two low notes at once will produce nonsense.
2. Start at the low E and work up. Same order every time means you notice immediately when something is unusually far out.
3. Turn slowly and finish from below. Bass tuners are geared low, so turns are gentle, but the principle holds: come up to the note so the string is seated under tension rather than resting on slack that will slip when you dig in.
4. Go round twice. Bass strings are under high tension and the neck responds to every change. The second pass is not optional.
5. Play the part you are about to play, hard, then check again. Slapping and hard fingerstyle pull strings out of tune much faster than gentle playing does, so a bass tuned gently and then attacked will drift within a minute.

Without a tuner: the fifth-fret method

Simpler on bass than on guitar, because there is no exception to remember. The note at the fifth fret of any string is the open note of the next string up.

1. Anchor the low E to something external: a piano, a drone, another instrument, the rest of the band. Everything below tunes the bass to itself, which is only useful alone.
2. 5th fret of E gives you A. Match the open A string to it.
3. 5th fret of A gives you D.
4. 5th fret of D gives you G. Done.
5. On a five-string, the B works the same way: 5th fret of B gives you E.

Listen for the wobble rather than trying to judge which note is higher. Play both together and you will hear a slow pulsing that gets slower as the two converge and stops when they match. Down at bass frequencies this beating is unusually easy to hear, which makes tuning by ear practical on this instrument.

Drop D, five strings, and tuning down

Drop D lowers the low E a whole tone to D (36.71 Hz), leaves everything else alone, and gives you a lower root plus a one-finger fifth across the bottom two strings. Ten seconds each way.

Half step down (E♭ A♭ D♭ G♭) moves everything a semitone, changes no relationships, and exists mostly to match guitarists and recordings that did the same. Whole step down starts to want heavier strings.

Five-string basses add a low B rather than tuning anything differently, and the B string is where cheap instruments show their limits: it needs enough scale length and enough tension to speak clearly rather than flop. If your B sounds mushy and reads badly, that is usually the instrument or the string gauge, not your tuning.

If you are tuning down purely to play along with a recording, consider shifting the recording instead. It is a second's work and leaves your bass alone. See changing the key of a video.

In tune and still not sitting right

On bass, the most common cause of “in tune but wrong” is intonation, and it shows up worse than on guitar because the strings are thicker and the errors are bigger. Compare an open string to its 12th-fret note: same letter, one octave apart. If the fretted note is sharp, the saddle needs to move back. Heavy-handed fretting is the other culprit: a thick string pressed hard behind the first few frets goes noticeably sharp, and a bass player with a strong left hand can be a full ten cents out without touching a tuning peg.

Then lock in with the drummer

Bass is the instrument where pitch and time meet, and a bass that is fractionally out of tune muddies the whole band's low end in a way nobody can identify but everybody hears. Tune properly, then spend the session on the other half of the job: the click, and the tempo you can actually play cleanly.