如何線上為吉他調音:完整指南

Tuning a guitar used to require either a perfect ear or a $50 clip-on tuner. Today, any browser with microphone access can do the job for free in under a minute. This guide explains standard guitar tuning, how online tuners work, and how to keep your guitar in tune longer.

Standard Tuning EADGBe Explained

A standard 6-string guitar is tuned, from lowest string (thickest) to highest (thinnest): E2, A2, D3, G3, B3, E4. Musicians abbreviate this as "EADGBe" with the lowercase e indicating the high E string. These five intervals: perfect fourth, perfect fourth, perfect fourth, major third, perfect fourth: form the basis of every standard chord shape you'll learn.

You can verify this on our free tuner. Each string lights up its target note when plucked:

Tuning by Ear vs Online Tuner

Professional musicians tune by ear because it's faster and works without any tools. They use the 5th fret method: fret the low E at the 5th fret: it should match the open A string. Then fret the A at the 5th fret to match D, and so on (with the exception of the G–B pair, which uses the 4th fret).

For beginners, this method requires ear-training you don't have yet. An online tuner removes ambiguity: pluck a string, see exactly how much higher or lower you need to adjust. As your ear develops, you can do progressively more by ear and use the tuner only for verification.

How to Use an Online Guitar Tuner

Allow microphone access when the page prompts. Pluck the low E string firmly and let it ring. The tuner detects the pitch and displays the nearest note with a needle showing how far above or below the target you are. Adjust the tuning peg until the needle centers.

Repeat for A, D, G, B, and high e. After all six are in tune, go back and re-check the low E: adjusting strings changes neck tension slightly, which subtly detunes the others.

Common Tuning Problems

String slips out of tune as you play: the string is wound poorly at the tuning post. Restring with 2–3 wraps around the post for better hold.

String stays in tune open but is sharp when fretted: intonation is off. Adjust the saddle position at the bridge to move the contact point and correct it.

Tuner shows wildly wrong notes: harmonics are confusing it. Pluck cleanly without finger noise, and try plucking closer to the bridge rather than over the soundhole.

Alternate Tunings Overview

Once standard tuning feels comfortable, alternate tunings unlock new sounds. Drop D drops the low E to D, giving instant power chords and a deeper sound. Open G (DGDGBD) is the slide-blues classic. DADGAD is the Celtic and folk staple. Each tuning unlocks different chord shapes and song repertoires.

How Often to Tune

A well-set-up guitar with fresh strings can stay in tune for a full hour-long practice session. New strings stretch and detune constantly for the first few hours: be patient. After a week of regular play, tuning should hold for an entire session.

Temperature and humidity affect tuning most. A guitar moved from a cold car to a warm room will need re-tuning. Use a hard case with a humidifier to minimize these issues.

String Care Tips

Wipe strings down after every play session: sweat corrodes wound strings within weeks. Replace strings every 1–3 months for daily players, every 6 months for occasional players. Old strings sound dull, lose intonation, and break unpredictably.