Bass Tuner
Four or five string, down to a low B — tuned through your microphone, with the audio analysed on your device and never recorded.
Table of contents
Why a bass is harder to tune than a guitar
A low E on a bass repeats about 41 times a second, and a five-string’s low B only about 31. That sounds like a detail and is the whole difficulty: to measure a pitch you need several repetitions of it, so a low B needs roughly a fifth of a second of audio before there is anything to measure. Everything about a bass tuner is slower than a guitar tuner for that reason alone.
The fundamental is also the quiet part. On a plucked bass string the harmonics above the note frequently carry more energy than the note itself, and a small speaker or laptop microphone may barely reproduce the fundamental at all. Pitch detection that follows the loudest repetition therefore reports the octave above — which is the single most common wrong answer a bass player gets from a tuner.
This one measures the signal against a delayed copy of itself and divides out its own energy at each candidate period, so a loud harmonic does not outweigh a quiet fundamental, and then takes the first plausible period rather than the strongest. That is the difference between reading a low B as B0 and reading it as B1.
Practically: pluck nearer the bridge for a clearer fundamental, let the note ring rather than damping it, and give the reading a moment to settle before you judge it.
Frequently asked questions
Yes. The detector searches down to 28 Hz, comfortably below the 30.9 Hz of a low B, and the five-string tuning is in the instrument list. It is the hardest note on the instrument to measure, so give it a firm pluck and a second to settle.
Because the fundamental of a plucked bass string is often quieter than the harmonic above it, and simpler detection follows whichever repetition is strongest. This tuner normalises by the signal's own energy at each candidate period and prefers the first plausible one, which is what stops that error.
Acoustically is fine and is what the microphone hears. An unplugged electric bass is quiet but well within range — hold it near the device, away from anything humming, and pluck firmly.
The attack of a plucked bass note is a mess of harmonics and string noise that settles into a clear pitch after a moment. Wait for the note to bloom rather than reading the instant you pluck, and it will steady.
Usually new strings still stretching, or the neck responding to a change in temperature or humidity. Stretch new strings by hand and retune several times over the first hour. If it drifts sharp and flat between sessions with old strings, it is the neck moving, not the tuning.
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