Related

RegisterClefConcert PitchTimbreArticulation MarksHarmonic SeriesAcoustic GuitarUkuleleMandolinLute

The classical guitar is a six-string instrument held in the lap and plucked with the fingertips. Everything about it serves one purpose: to turn the vibration of six strings into a sound in which several voices can be heard at once.

It is also the most traditional member of the guitar family: nylon strings, fan bracing, fingernails rather than a pick, and notation an octave above sounding pitch.

Structure: why a guitar's waist is so shallow

That last line is the key fact of this section. Set the three side by side (measured data):

A violin's waist is cut deep (0.32) because it is bowed — the bow has to pass through the waist. A guitar's waist is shallow (0.47) because it is plucked by hand, and the hand only needs room to sweep across the strings. The area it saves goes straight into the top plate. Area is volume.

How it sounds: fan bracing is built for nylon

The acoustic path is the same as a violin's: string → bridge → top plate → air in the box → out through the soundhole. What differs is the wood on the inside of the top plate.

Nylon strings pull far less than steel — about 40 kg for all six, roughly half of a steel set. Less tension means less force pushing the top plate, so a classical guitar uses fan bracing: several thin struts spreading outwards from below the soundhole, distributing the force over a wide area so the whole plate vibrates as evenly as possible.

(For comparison, steel-string guitars use X-bracing — two main braces crossing. Steel pulls twice as hard, so the plate needs to resist rather than spread. See acoustic guitar.)

The soundhole is an opening, not decoration: the air inside acts as a Helmholtz resonator, at roughly 100 Hz. The guitar's lowest open string, E2, is 82 Hz — below the resonance. So the guitar's lowest notes are inherently thin. No guitar escapes this; it is a physical limit, not a matter of price.

Range

吉他是移调乐器 —— 记谱比实音高一个八度。上面一行是记谱，下面一行是实际听到的音高。

The six strings are tuned E2–A2–D3–G3–B3–E4: every adjacent pair is a fourth except G to B, which is a third. That exception is a historical inheritance — it was kept because it lets chord shapes move across the neck, and the price is that scale patterns change shape at the G–B boundary.

One useful consequence: the lowest four strings (E A D G) are all a fourth apart, the same logic the violin family uses — so a guitarist picking up a bass can transfer those fingerings directly.

Timbre, and how to hear it

How to recognise a classical guitar:

1. The attack is fingernail, not pick. There is a small high-frequency click at the pluck, but rounder and softer than a steel string's or a pick's. It is the first identifying feature. 2. The decay is faster but cleaner than steel. Nylon has higher internal damping, so the sound does not trail the long metallic overtone tail that steel strings do. 3. The bass strings do not boom. E2 and A2 are thin (the soundhole-resonance issue above). A good player compensates with rest strokes, but only partly — it is a design characteristic, not a fault. 4. Harmonics are clear. Because the whole plate vibrates, the natural harmonics at frets 12, 7 and 5 ring out very cleanly, sounding almost like another instrument.

The player below gives the six open strings, lowest to highest. Notice that the bottom two (E2, A2) sound thinner than the rest — that is the box resonance sitting above them.

The tracks under “Listen in the library” are the skeleton of the music — transcription or engraving MIDI — while timbre is handled by the player above.

Playing techniques

The right hand uses no pick: the thumb (p) and the index, middle and ring fingers (i, m, a) divide the work. That is the practical meaning of "classical" in the name — the right hand is a system.

• Rest stroke (apoyando) and free stroke (tirando): in a rest stroke the finger comes to rest on the next string — fuller, better for melody; in a free stroke it lifts away — lighter, better for fast figures. These two are the grammar of the right hand.
• Tremolo: the thumb plays the bass while i, m and a repeat the same high note, so it sounds like one long note. A signature technique.
• Hammer-ons and slides (left hand): sounding a note by hammering a finger onto the fret, or sliding into it, without plucking.
• Natural and artificial harmonics: touch the string lightly at fret 12, 7 or 5; or stop with the left hand and touch a node with the right.
• Muting: the side of the right palm near the bridge gives a damped or staccato sound.

Because there is no pick, a classical guitar is generally quieter than a steel-string, but it has finer dynamic shading — it can fade to a very soft pianissimo, which a pick makes difficult.

The family

The guitar line and the pick line are easy to confuse:

Two decisive differences: plucked by finger or by pick; single strings or doubled courses. Doubled courses (mandolin, lute) make each note thicker and longer, at the cost of twice the tuning and restringing work.

Chasing the guitar's ancestry leads to the lute. The essential change from lute to guitar was replacing doubled courses with single strings: fewer strings, more volume, easier tuning.

History

The guitar family's root is the lute. In 16th-century Spain a smaller instrument with four doubled courses appeared — the vihuela — and it replaced the lute's tuning with the guitar logic (fourths plus one third). That choice survives today: the guitar's tuning is Spanish, not general European practice.

Three centuries of adding strings followed: four courses → five courses → five single strings (16th c.) → six single strings (around the end of the 18th c.).

The decisive fixing happened in 19th-century Spain. The maker Torres enlarged the body to a new proportion — today's "classical guitar size" is his — and established fan bracing. Since then the instrument has barely changed: a guitar built now has almost the same outside shape and inside structure as one built 150 years ago.

The 20th century split it into two traditions: performing (Segovia put the classical guitar on the solo stage) and writing (from Tárrega and Barrios to composers working today). It is one of the few plucked instruments with both a complete teaching method and a living contemporary repertoire.

Common misconceptions

• "A classical guitar can only play classical music." "Classical" names the hold and the right-hand technique, not a repertoire. Contemporary works, jazz arrangements and folk music all get played — with the same hand.
• "Nylon is inferior to steel; less volume means worse." The two string types match two structures: low tension needs fan bracing to spread the force; high tension needs X-bracing to resist it. Lower volume is the price of trading tension for finer dynamics, not a rank.
• "Six strings means it covers more than a violin." More strings is not more range. A guitar sounds E2–E6 (about four octaves); a violin is G3–E7 — the violin goes higher. What the guitar adds is the ability to sound several notes at once.
• "Frets make intonation a solved problem." Frets quantise pitch onto the twelve-tone grid. You cannot play another temperament, or slide — exactly why unfretted instruments such as the violin exist.
• "What you read is what sounds." Backwards. The guitar is a transposing instrument, notated an octave above sounding pitch. The two rows on the range chart show it.
• "More strings is simply better." Seven- and eight-string guitars do extend the bass, but doubled courses (as on a mandolin) do not mean more volume — that is a different trade-off, see mandolin.

Next

To keep listening: go to the acoustic guitar — same shape, a different set of strings and a different bracing pattern. Hearing the two side by side makes "structure follows the strings" audible. Then trace the ancestry to the lute and see what the guitar's doubled-course ancestor looked like. :::

Sources

• 琴体尺寸取通行制琴数据：琴体长 480 毫米、上腰宽 285、腰宽 225、下腰宽 355 毫米，弦长 650 毫米
• 定弦 E–A–D–G–B–E（除三度外均为四度）与「记谱比实音高一个八度」属通行乐器学常识，本文为原创表述
• 扇形音梁（fan bracing）为尼龙弦吉他常用结构、X 形音梁为钢弦吉他常用结构，依通行制琴工艺叙述
• 音域数据依通行乐谱与乐器词典，本文为原创表述

Used for fact-checking only; all prose is original.