Mar 25, 2026

What Are Extended Range Guitars and Why Are Musicians Obsessed?

Standard guitars have six strings. That has been true for over two centuries, and for most players, those six strings provide more musical possibilities than a lifetime of practice could fully exhaust. Yet a growing number of guitarists have decided that six strings are not enough - and the extended range guitar market has grown rapidly as a result.

Extended range guitars, often abbreviated as ERGs, go beyond the standard six-string format by adding one or more additional strings to expand the instrument's pitch range. Seven-string and eight-string electric guitars are the most widely recognized examples, but the concept of extending a guitar's range is older and broader than the modern metal scene that brought these instruments into mainstream awareness.

This guide explains what extended range guitars are, why players use them, how the different formats compare, and - importantly - how the concept of extended range applies to acoustic instruments, including Timberline's harp guitar series.

What Is an Extended Range Guitar?

An extended range guitar is any guitar designed to go beyond the pitch boundaries of a standard instrument. Most commonly, this means adding strings below the standard low E string to reach lower pitches that would otherwise require a bass guitar. Less commonly, strings are added above the high E string to extend the treble range.

The standard six-string acoustic or electric guitar spans approximately two octaves, from low E2 to around high E5 depending on the number of frets. An extended range guitar stretches this window - downward, upward, or in some designs, both directions simultaneously.

It is worth noting that a 12-string guitar, while technically having more strings than a standard guitar, is not classified as an extended range guitar. On a 12-string, each of the six standard strings is paired with a companion string tuned in unison or an octave above. The pitch range remains the same as a six-string - only the harmonic texture changes. A true extended range guitar adds strings that go beyond the pitch range of a standard instrument.

Types of Extended Range Guitars

7-String Guitars

The seven-string electric guitar is the most common and accessible entry point into extended range instruments. The additional string is typically positioned below the low E and tuned to B1 - one step below the lowest note on a standard bass guitar's highest string. The remaining six strings stay in standard tuning, which means existing chord shapes, scales, and patterns transfer directly to the seven-string with no relearning required.

The low B string opens up a range of new possibilities including deep single-note riffs that sit below what a standard guitar can reach, chord voicings that incorporate a resonant bass note without requiring a bass player, and melodic movement between the bass range and the standard guitar range within a single instrument.

Ibanez introduced the first mass-produced seven-string solid body electric guitar, the Universe UV7, in 1990 in collaboration with Steve Vai. The instrument attracted only modest attention initially, but by the mid-1990s bands like Korn, Dream Theater, and Meshuggah had adopted seven-string guitars and established the format as central to progressive and heavy metal music.

8-String Guitars

Eight-string guitars add a second additional string below the low B of a seven-string, typically tuned to F#1 - which sits in the frequency range of a bass guitar's lowest register. This gives the player access to extraordinarily low pitches that overlap with the bass guitar's range while maintaining the full range of a standard six-string above.

The eight-string format is closely associated with the djent subgenre of progressive metal, which developed in the early 2000s around the heavily distorted, palm-muted, rhythmically complex playing style pioneered by bands including Meshuggah, Periphery, and Animals as Leaders. The extended low range gives djent players the deep, percussive low-end that defines the genre's sound.

Eight-string guitars typically require longer scale lengths than standard guitars - 27 inches or more is common, compared to the standard 25.5 inches - to maintain adequate string tension on the lowest strings at such low pitches.

9-String and Beyond

Nine-string and ten-string guitars exist and are used by a small number of highly specialized players. Meshuggah briefly used nine-string guitars before settling on eight-string instruments. These extreme configurations are rare, purpose-built for specific sonic goals, and represent a very small segment of the extended range market.

Multiscale (Fan Fret) Guitars

Multiscale guitars address a fundamental acoustic challenge with extended range instruments: the lowest strings require a longer vibrating length to maintain proper tension and intonation, while the highest strings work best at a standard scale length. A multiscale guitar uses two different scale lengths - a longer one for the bass strings and a shorter one for the treble strings - with the frets angled or fanned across the fretboard at a graduating angle to accommodate both. This design allows extended range guitars to maintain accurate intonation and proper playability across the full string range.

Standard Tunings by String Count

Understanding what each format is tuned to is essential for evaluating whether an extended range guitar matches your musical goals:

Format	Standard Tuning (low to high)	Added Range	Primary Genre Use
6-String (standard)	E2-A2-D3-G3-B3-E4	Baseline reference	All genres
7-String	B1-E2-A2-D3-G3-B3-E4	Low B below standard range	Metal, prog, jazz
8-String	F#1-B1-E2-A2-D3-G3-B3-E4	Low F# into bass register	Djent, prog metal, fusion
Baritone 6-String	B1-E2-A2-D3-F#3-B3 (typical)	Tuned down as a whole	Country, metal, film scoring
Acoustic Harp Guitar	Variable sub-bass strings + standard 6	Dedicated sub-bass register	Fingerstyle, classical, folk

Why Musicians Are Obsessed with Extended Range Guitars

Greater Compositional Freedom

The most straightforward appeal of an extended range guitar is pure musical possibility. Having access to lower pitches that would otherwise require a second instrument means a single guitarist can write and perform music that covers more of the frequency spectrum. A seven-string player can lay down a deep bass riff with the left hand while playing a melody on the higher strings - something that requires two separate instruments in a standard setup.

For composers and solo performers, this expanded range translates directly into richer, more complete musical arrangements. The additional strings are not just lower notes - they are an entirely new dimension of harmonic and rhythmic possibility.

The Pull of the Low End

There is a visceral appeal to low-frequency sound that is deeply ingrained in modern music. The heaviness that defines metal, the groove that drives funk and hip-hop, the depth that gives film scores their emotional weight - all of these rely heavily on low-frequency content. Extended range guitars give guitarists direct access to that low-end territory without handing the frequency to a bassist or keyboard player.

The physical sensation of playing a heavily distorted low B or F# string through a high-gain amplifier is genuinely distinct from anything a standard six-string can produce. For metal players in particular, this is not just a tonal preference - it is a fundamental part of the genre's identity.

Influence of Progressive and Metal Pioneers

The mainstream adoption of extended range guitars was driven largely by the influence of pioneering bands whose creative output inspired a generation of players to pick up seven and eight-string instruments. Meshuggah's use of eight-string guitars to create their signature polyrhythmic, heavily downtuned sound directly inspired the djent movement. Periphery and Animals as Leaders demonstrated that extended range instruments could produce music of extraordinary technical and compositional sophistication. Tosin Abasi of Animals as Leaders introduced a percussive thumb-slapping technique adapted from bass guitar onto the eight-string guitar, expanding what the instrument was thought capable of producing.

Each of these artists developed a personal voice on the extended range guitar that could not have existed on a standard six-string, and that originality inspired widespread adoption of the format.

Modern Music Production Demands

In recorded music production, the extended range guitar has become a standard tool for achieving low-end clarity and separation in dense mixes. A downtuned seven or eight-string guitar can occupy a frequency range that sits between a standard guitar and a bass guitar, creating layered tonal textures that are difficult to achieve any other way. Studio producers working in metal, progressive rock, and experimental music have incorporated extended range guitars as a standard part of the sonic palette.

The Challenges of Extended Range Guitars

The appeal of extended range guitars is real, but so are the challenges. Players considering their first seven or eight-string instrument should be aware of what the transition involves.

• Wider neck: Each additional string requires more fretboard width. A seven-string neck is noticeably wider than a standard six-string, and an eight-string is wider still. Players with smaller hands may find the reach across the full neck challenging, particularly in the lower fret positions

• Increased weight: The larger body and neck required by additional strings make extended range guitars heavier than standard instruments. Long playing sessions can become physically tiring more quickly

• Intonation complexity: Achieving accurate intonation on the lowest strings requires careful setup by a qualified guitar technician. Lower-tuned strings with thicker gauges are more sensitive to intonation problems than standard strings

• Fewer repertoire resources: While the extended range guitar community is large and active online, published learning resources, instructional books, and formal method materials are far less plentiful than for standard six-string guitar

• Mental adjustment: The additional string can be disorienting for experienced six-string players who have built strong muscle memory. The standard strings are in the same positions, but the presence of an additional string changes the spatial relationship between the strings during playing

Extended Range in Acoustic Guitars: The Harp Guitar

The electric guitar world has largely defined the modern conversation around extended range instruments, but the concept of extending an acoustic guitar's range has existed for far longer. The harp guitar is the acoustic world's answer to the extended range guitar - and in many ways it is a more radical extension than adding one or two strings to an electric.

A harp guitar combines a standard six-string guitar with a set of additional sub-bass strings that are not fretted. These extra strings - typically six to twelve in number depending on the instrument - are mounted on an extended arm attached to the guitar body and are plucked open by the thumb of the picking hand to produce resonant bass drones and walking bass lines that accompany the fretted melody and chord playing on the standard strings.

The harp guitar has a documented history stretching back to the early nineteenth century in Europe, where luthiers built instruments with additional bass courses for parlor music performance. In America, the harp guitar reached peak popularity in the late nineteenth and early twentieth centuries through the instruments built by the Larson Brothers and others.

Timberline Harp Guitars: Acoustic Extended Range Done Right

Timberline Guitars builds two harp guitar models that represent the acoustic extended range concept at a high level of craftsmanship. Both instruments combine a full-size acoustic guitar with additional sub-bass strings designed for fingerstyle playing.

• T20HGpc: Timberline's entry-level harp guitar features a solid spruce top and solid mahogany back and sides, with six sub-bass strings providing drone tones and bass lines below the standard six-string register. The arm bevel - Timberline's signature comfort feature - is standard on this model, making extended playing sessions with the instrument's unusual size and string layout significantly more comfortable

• T80/20HGc-e: Timberline's premium harp guitar features upgraded tonewoods, the same six sub-bass string configuration, and an onboard electronics system for live performance. This model brings the full extended range acoustic concept to performance and recording contexts

The Timberline harp guitar occupies a completely different musical space than a seven or eight-string electric guitar. Where the electric extended range instruments pursue heaviness and low-frequency power, the acoustic harp guitar pursues harmonic richness and the simultaneous independence of bass, rhythm, and melody voices in a fingerstyle setting. Both are expressions of the same fundamental desire: more musical range from a single instrument.

Is an Extended Range Guitar Right for You?

The answer depends on the music you want to play and the problems you are trying to solve with your instrument.

An extended range electric guitar makes strong sense if you regularly play music that uses downtuned riffs in the low B or F# range, if you compose music that requires a bass-range instrument and a guitar-range instrument simultaneously, or if you play in a small ensemble where covering more of the frequency spectrum with a single instrument has practical value.

An extended range acoustic guitar - specifically a harp guitar - makes sense if your playing is fingerstyle-based, if you want to perform full arrangements as a solo performer without a bassist, or if you are drawn to the historic and contemporary fingerstyle tradition that the harp guitar occupies.

Neither type of extended range guitar is a substitute for developing strong technique on a standard six-string first. The additional strings on any extended range instrument are most useful to a player who already understands the standard range well enough to make meaningful use of the extension.

Frequently Asked Questions

What is the difference between a 7-string and an 8-string guitar?

A seven-string guitar adds one string below the standard low E, typically tuned to B1. An eight-string adds a second additional string below that, typically tuned to F#1. The eight-string reaches into the bass guitar's frequency range and requires a longer scale length - usually 27 inches or more - to maintain proper string tension on the lowest strings. Seven-string guitars are more accessible for players transitioning from a six-string, while eight-string instruments have a steeper adjustment curve.

Are extended range guitars only for metal players?

No. While the modern extended range electric guitar market is dominated by metal, progressive rock, and fusion players, seven and eight-string guitars are used in jazz, classical, and experimental music as well. Jazz guitarists like Bucky Pizzarelli have played seven-string instruments since the 1950s. On the acoustic side, harp guitars are used exclusively in fingerstyle, folk, and classical contexts and have no connection to the metal world.

Is a 12-string guitar an extended range guitar?

Not in the technical sense. A 12-string guitar pairs each of the six standard strings with a companion string tuned in unison or an octave above, creating a richer, chorus-like tone. The pitch range remains the same as a standard six-string. A true extended range guitar adds strings that go beyond the pitch boundaries of the standard instrument - lower or higher notes, not doubled existing ones.

What is a multiscale or fan-fret guitar?

A multiscale guitar uses two different scale lengths across the fretboard - a longer scale on the bass side and a shorter scale on the treble side - with the frets angled to accommodate both. This design allows the lower strings to achieve proper tension and intonation at low tunings while the higher strings remain comfortable to play at a standard scale length. Multiscale guitars are especially common on eight-string and nine-string instruments where the range of string gauges and tensions is most extreme.

How does Timberline's harp guitar compare to a 7-string electric as an extended range instrument?

They share the concept of extending pitch range beyond a standard guitar but serve entirely different musical purposes. A seven-string electric guitar extends the range downward for heavily distorted, high-gain playing in metal and progressive rock. Timberline's harp guitar extends the range into the sub-bass register for fingerstyle acoustic playing, adding harmonic depth and bass accompaniment to a solo fingerstyle performance. One is built for power and heaviness; the other is built for tonal richness and musical independence in an acoustic setting.