Recent from talks
Nothing was collected or created yet.
Fingerboard
View on WikipediaThe fingerboard (also known as a fretboard on fretted instruments) is an important component of most stringed instruments. It is a thin, long strip of material, usually wood, that is laminated to the front of the neck of an instrument. The strings run over the fingerboard, between the nut and bridge. To play the instrument, a musician presses strings down to the fingerboard to change the vibrating length, changing the pitch. This is called stopping the strings. Depending on the instrument and the style of music, the musician may pluck, strum or bow one or more strings with the hand that is not fretting the notes. On some instruments, notes can be sounded by the fretting hand alone, such as with hammer ons, an electric guitar technique.
The word "fingerboard" in other languages sometimes occurs in musical directions. In particular, the direction sul tasto (Ital., also sulla tastiera, Fr. sur la touche, G. am Griffbrett) for bowed string instruments to play with the bow above the fingerboard. This reduces the prominence of upper harmonics, giving a more ethereal tone.[1]
Frets
[edit]
A fingerboard may be fretted, having raised strips of hard material perpendicular to the strings, which the player presses the strings against to stop the strings. On modern guitars, frets are typically made of metal. Frets let the player stop the string consistently in the same place, which enables the musician to play notes with the correct intonation. As well, frets do not dampen string vibrations as much as fingers alone on an unfretted fingerboard. Frets may be fixed, as on a guitar or mandolin, or movable, as on a lute. Fingerboards may also be unfretted, as they usually are on bowed instruments, where damping by the finger is of little consequence because of the sustained stimulation of the strings by the bow. Unfretted fingerboards allow a musician more control over subtle changes in pitch than fretted boards, but are generally considered harder to master. Fingerboards may also be, though uncommon, a hybrid of these two. Such a construction is seen on the sitar, where arched frets attach at the edges of a smooth fingerboard; unfrettable strings run inside the frets, while frettable ones run outside. The fret arches are sufficiently high that the exterior strings can be fretted without the finger making contact with the interior strings.
Frets may be marked by inlays to make navigating the fingerboard easier. On six-string guitars and bass guitars, markers are typically single smallish dots on the fingerboard and on its side that indicate the 3rd, 5th, 7th and 9th frets—and the octaves of those positions higher up the neck. A double dot or some other variation marks the 12th fret and 24th frets. Variations on the standard dot shape can make a guitar more distinctive. Position markers are sometimes made luminescent (through using paint, or illuminated with light emitting diodes) to make them more visible on stage. Position markers are also sometimes repeated on the edge of the fingerboard for easy viewing.
Over time, strings wear frets down, which can cause buzzing and deaden the sound. Fixing this occasionally requires replacing the frets—but more often they just need "dressing". In fret dressing, a luthier levels and polishes the frets, and crowns (carefully rounds and shapes) the ends and edges. Stainless steel guitar frets may never need dressing, because of the density of the material.[2] Not having frets carefully and properly aligned with the fingerboard can cause severe intonation issues and constant detuning. The ultimate way of determining the source of a buzz and detuning problem is to measure the levelness of the frets. A straightedge positioned on the neck in the "lie" of one of the strings should show nearly level frets. (There should be a slight relief to compensate for the elliptical shape of the vibrating strings.)
Materials
[edit]On bowed string instruments, (such as violin, viola, cello, and double bass), the fingerboard is usually made of ebony, rosewood or other hardwood. On some guitars, a maple neck and fingerboard are made from one piece of wood. A few modern luthiers have used lightweight, non-wood materials such as carbon-fiber in their fingerboards.[3] Various impregnated wood materials are being used for fingerboards in fretted instruments.[4]
Parameters
[edit]
Typically, the fingerboard is a long plank with a rectangular profile. On a guitar, mandolin, ukulele, or similar plucked instrument, the fingerboard appears flat and wide but may be slightly curved to form a cylindrical or conical surface of relatively large radius compared to the fingerboard width. The radius quoted in the specification of a string instrument is the radius of curvature of the fingerboard at the head nut.
Most bowed string instruments use a visibly curved fingerboard, nut and bridge to provide bow clearance for each individual string.
The length, width, thickness and density of a fingerboard can affect timbre. Most fingerboards can be fully described by these parameters:
- w1 — width at nut (close to the headstock)
- w2 — width at half of scale length (if fretted, usually the 12th fret)
- h1 — profile height (thickness) at the nut
- h2 — profile height (thickness) at half of scale length
- r — radius (may be non-constant)
Radius
[edit]
Depending on values of radius r and their transition over the length of the fingerboard, all fingerboards usually fit into one of the following four categories:
| 1 | Flat | Both nut and bridge are flat. The strings are all in one plane, and the instrument does not have a radius (the radius is in a sense infinite). | |
|---|---|---|---|
| 2 | Cylindrical | The fingerboard has a constant radius, and the fingerboard, the nut and the bridge all have the same nominal radius (that of the fingerboard is strictly speaking a little smaller than that of nut and bridge). | |
| 3 | Conical | The fingerboard has a varying radius, usually linearly progressing from to . Sometimes it is also called a compound radius.[5] The nut and bridge are both curved but the nut radius is smaller than that of the bridge. | |
| 4 | Compound | While not strictly conical, with a curved nut and linear bridge. All parts of the fingerboard have some curvature, but the fingerboard shape is not strictly a cone. | , usually |
Notes:
- is a scale.
- designates a place on fingerboard, changes from 0 (at nut) to (at bridge).
- describes radius depending on place on fingerboard.
- is a non-linear function.
Classical guitars, some 12-string guitars, banjos, dobros, pedal steel, and a few steel-stringed acoustic guitars have flat fingerboards. Almost all other guitars have at least some curvature. However, some recent five and six string electric basses have flat fingerboards.
For guitars, some players feel that smaller radii (7.25–10") are more comfortable for chord and rhythm playing, while larger radii (12"-16" and up to flat) are better for fast soloing. Conical and compound radius fingerboards try to merge both these features. The nut end of the fingerboard has a smaller radius to ease in forming chords. The bridge end of the fingerboard has a larger radius to make soloing more comfortable and prevent "noting out"[6] ("fretting out"), in which a string comes in contact with a higher fret during bends.
A Brief History Of Discovering The Conical Fingerboard in 1978 by luthier Denny Rauen can be found in American Lutherie #8/Winter 1986 and String Instrument Craftsman May/June 1988 under the title "Multi-Radius Fingerboards". This special radiusing is a standard on many of Denny's custom-built guitars and refret work beginning in 1978. Denny Rauen's articles on the "Multi Radius Fingerboard" are the first published documents on using a conical fingerboard to improve string bending while retaining comfortable chording.
Bowed string instruments usually have curved fingerboards, to allow the player to bow single strings. Those of the modern violin family and the double bass are strongly curved, however those of some archaic bowed instruments are flat.
Examples
[edit]This section needs additional citations for verification. (May 2023) |
Examples of some instruments' fingerboard radius parameters:
| Model | radius |
|---|---|
| Fender vintage guitars | 7.25 in (184.1 mm) |
| Fender modern guitars | 9.5 in (241 mm) |
| Gibson electric guitars | 12 in (305 mm) |
| Gibson acoustic guitars | 12 in (305 mm) |
| Martin acoustic guitars | 16 in (406.4 mm) |
| Danelectro guitars | 14 in (355 mm) |
| Rickenbacker guitars | 10 in (254mm) |
| Jackson guitars | 16 in (406 mm) compound |
| PRS Guitars Regular[7] | 10 in (254 mm) |
| Classical guitars | flat (no radius) |
| Full size (4/4) violin | 42 mm |
Scalloping
[edit]
A fretted fingerboard can be scalloped by "scooping out" the wood between each of the frets to create a shallow "U" shape. The result is a playing surface wherein the players' fingers come into contact with the strings only, and do not touch the fingerboard.
The process of "scalloping" a fingerboard well, if done by hand, is tedious work, usually done by careful filing of wood between the frets, and requires a large investment of time. Consequently, it is relatively expensive to have done. Generally, luthiers scallop fingerboards with a special milling machine that has 22 or 24 (according to neck dimensions and number of frets) wood cutting tools. This equipment saves time and adds precision to the process of scalloping the wood in the neck's radius the same in all fret spaces.
Scalloped fingerboards are most commonly used by shred guitarists, most notably Ritchie Blackmore and Yngwie Malmsteen, who have signature models developed with Fender that include scalloped fingerboards. Ibanez JEM series guitars, designed and played by Steve Vai, come standard with the last 4 frets scalloped. In 2008 Ibanez made available their E-Gen model, a Herman Li signature, which includes four scalloped frets (21st to 24th). Karl Sanders of the death metal band Nile also uses several guitars with scalloped fingerboards, including several Deans, and KxK Guitars.
In the 1970s, English guitarist John McLaughlin played with Shakti, along with Indian violinist L. Shankar, using an acoustic guitar with a fully scalloped fretboard. He also used an electric guitar with a scalloped fretboard in studio and live performances from 1978 to 1979. McLaughlin explained that this feature increased the ease and range of string bends by eliminating friction between the finger and fretboard. The scalloped fretboard also facilitates the rapid, microtonal variation that is important in Indian music, as exemplified by classical Indian Sitar music. Without scallops, the guitarist must play microtones by sliding the string sideways on the fret.
Experimental luthier Yuri Landman made an electric guitar for John Schmersal of Enon called the Twister with a partial scalloped neck for only the thin strings (similar to small playground slides).
Some examples of lutes with scalloped fretboards include the South Indian veena and Vietnamized guitar (called đàn ghi-ta, lục huyền cầm, or ghi-ta phím lõm). The Japanese multi-instrumentalist and experimental musical instrument builder Yuichi Onoue has also made a deeply scalloped electric guitar for Vietnamese microtonal playing techniques.[8]
Some types of scalloping are:[9]
- Partial Scalloping, with some of the high frets scalloped for fast soloing. Popular examples include half scalloping (12th to the last fret, used by Kiko Loureiro of Megadeth,[10] among others) or upper fret scalloping (19–24, 17–22, etc.), used by such guitarists as Steve Vai. When done by hand, sometimes fretboards can be scalloped half below the D or G strings, as in the case for Turkish luthier Kenan Turgut.
- Full Scalloping, i.e., all frets from the first to the last are scalloped
- Extreme Scalloping scalloping has lateral intrusions in addition to the standard vertical hollows. The additional versatility in note control comes at the cost of substantially reduced rigidity of the neck.
Note that filing away wood to scallop a fingerboard also affects inlays—so intricately inlaid fingerboards are not usually good candidates for scalloping. Simple dot or block inlays survive the procedure moderately well.
Advantages and disadvantages
[edit]The "scooped out" nature of scalloped fingerboards creates a number of changes in the way the guitar plays. Most obvious is that the fingertip only contacts the string, not the fingerboard itself, creating less friction for bends and vibratos, which results in more overall control while playing. It also results in more weight-relief and less "neck-dive".
However, one of the main disadvantages is that many players, especially new players, may find a scalloped fingerboard too different, and difficult to play easily, especially if the strings are of a lighter gauge or the player tends to press too hard. It takes practice to play in tune on a scalloped fingerboard. The player must first become accustomed to not actually touching the fingerboard. Playing a scalloped fingerboard requires a careful application of pressure: Too much pressure raises the pitch of the fretted note to a sharp note, as during a bend, and too little pressure causes fret buzz. As a result, most guitar players use a traditional fingerboard on their instruments.[11]
Scoop of fretless bowed-string fingerboards
[edit]Fretless bowed-string fingerboards are usually scooped lengthwise in a smooth curve, so that if a straight edge is held next to the board parallel to a string, some daylight shows between them, towards the centre of the board. Usually the scoop is slightly greater on the bass side, less on the treble side of the fingerboard. Different string materials or different styles of playing may call for differing amounts of scoop. Nylon or gut strings require the most, and solid steel-core strings the least. A typical full-size (4/4) violin with synthetic-core G, D, and A strings shows 0.75 mm of scoop under the G string, and between 0.5 mm and zero scoop under the E, which is usually a solid steel core on modern instruments.
Dip of guitar fretboards
[edit]On guitars, specifically steel-string and electric guitars, the relief (or "dip") is adjustable by altering the tension on the steel truss rod inside the neck. Relaxing the truss rod allows the pull of the strings to increase the dip, and vice versa. Classical guitars do not need truss rods due to the lower tension of nylon strings but should still exhibit some degree of dip.
See also
[edit]Notes
[edit]- ^ Sadie, Stanley; Tyrrell, John, eds. (2001). "Sul tasto". The New Grove Dictionary of Music and Musicians (2nd ed.). London: Macmillan Publishers. ISBN 978-1-56159-239-5.[full citation needed]
- ^ McPartl, Frank (February 2019). "How to Fret Dress an Electric Guitar - [ Complete Fret Leveling Guide ] -". Guitar Repair Bench. Retrieved 2023-02-10.
- ^ Luthier David Rivinus' site Archived 2006-04-12 at the Wayback Machine explanation of why he doesn't use ebony fingerboards
- ^ Mottola, R.M. (20 October 2021). "3 - The Fretboard". Building the Steel String Acoustic Guitar. Amazon Digital Services LLC - Kdp. ISBN 978-1-7341256-1-0.
- ^ Guitar neck radius Archived 2012-05-01 at the Wayback Machine article at Warmoth
- ^ [1] Archived 2015-03-15 at the Wayback Machine Mottola, R. (2014). Guitar Fretboard Camber and Action in the Context of String Bending. Savart Journal, 1(4)
- ^ "PRS Guitars FAQ: What are the differences between necks you offer?". Archived from the original on 2009-08-06. Retrieved 2007-06-26.
- ^ "None". Archived from the original on November 8, 2015.
- ^ Scalloped Guitar Necks article at Warmoth
- ^ [2] Archived October 29, 2008, at the Wayback Machine
- ^ Ross, Michael (1998). Getting Great Guitar Sounds: A Non-technical Approach to Shaping Your Personal Sound. Hal Leonard Corporation. p. 15. ISBN 978-0-7935-9140-4.
References
[edit]- Stringworks U brief description of fingerboard for violins, violas, & cellos
- Violin construction detailed specification sheet by Alan Goldblatt (PDF, 18KB)
- Fretboard Repair article explains common fretboard problems and repairs on the Guitar Repair Bench Luthier Website
- Ibanez website gives specific neck/fingerboard dimensions
- The Scalloped Fretboard Guitar article
Fingerboard
View on GrokipediaOverview and Function
Definition and Basic Components
A fingerboard, also known as a fretboard, is the surface on the neck of a stringed musical instrument, such as the guitar or violin, against which performers press the strings with their fingers to alter pitch and produce different notes.[1] It typically consists of a long, narrow strip of wood attached longitudinally to the instrument's neck, providing a smooth playing surface over which the strings are stretched.[8] The primary components of a fingerboard include its main longitudinal strip, often made of ebony or rosewood for durability and playability.[9] On many fretted instruments, inlaid position markers in the form of dots are embedded at standard locations such as the 3rd, 5th, 7th, 9th, and 12th frets to help musicians orient themselves quickly during performance.[10] At the upper end of the fingerboard, the nut—a small, hard ridge—anchors the strings in grooves, spacing them evenly and defining one end of their vibrating length, while the strings extend over the fingerboard to the bridge at the lower end, which anchors the opposite side.[11] Frets, optional raised metal strips embedded perpendicularly into the strip, are present on many instruments to mark semitone divisions precisely.[12] Fingerboards emerged on early necked string instruments such as lutes in the medieval period, with refinements in European lutherie during the Renaissance for instruments like viols.[13]Role Across String Instruments
The fingerboard serves as the primary interface for pitch alteration on string instruments, where pressing a string against it shortens the vibrating length between the nut and bridge, thereby raising the pitch from the open string's fundamental frequency.[14] Open strings, unstopped by the fingerboard, vibrate at their full length, producing the instrument's baseline tones without alteration.[14] This mechanism is common across bowed and plucked string instruments with necks, enabling musicians to access the full chromatic scale through precise finger positioning.[15] The fingerboard facilitates key performance techniques that enhance expressive control. Intonation relies on accurate finger placement to achieve precise pitches, a skill honed through left-hand positioning on the board.[15] Vibrato introduces subtle pitch oscillations by rocking the finger or hand against the string, adding warmth and emotional depth to sustained notes.[16] Harmonics are produced by lightly touching the string at nodal points on the fingerboard, isolating overtones while suppressing the fundamental.[14] Slides and glissandi involve gliding the finger along the fingerboard to create continuous pitch transitions, seamlessly connecting notes for melodic fluidity.[17] Frets, when present, aid consistent intonation by providing fixed reference points for finger placement.[18] Acoustically, the fingerboard's role stems from the physics of standing waves on strings, where pitch is governed by the fundamental frequency of vibration. The frequency of a string fixed at both ends (nut and bridge) is determined by its length , tension , and linear mass density , as derived from the one-dimensional wave equation . For the fundamental mode, the wavelength , and since wave speed , it follows that [19] Pressing the string shortens , inversely increasing to raise pitch, while tension and mass provide baseline tuning.[19] This principle underpins all fingerboard interactions, from subtle variations in bowed instruments to rapid changes in plucked ones.[19] Historically, the fingerboard evolved from tied-gut frets on Renaissance lutes, which fixed pitches for consistent intonation in polyphonic music, to the extended, often fretless boards of modern instruments.[20] By the 16th century, European lutes featured longer necks with multiple courses, allowing greater pitch range via fingerboard pressure.[21] This design influenced the guitar's development, transitioning from lute-like short-necked forms in the Renaissance to the six-string classical guitar by the 19th century, with raised fingerboards enhancing playability.[22] In contemporary electric guitars, the fingerboard supports amplified expression, where techniques like bends and slides are magnified electronically for dynamic solos and effects.[18]Materials and Construction
Common Materials
Fingerboards are traditionally crafted from dense hardwoods prized for their durability, smooth playability, and acoustic contributions. Ebony (Diospyros spp.), particularly African ebony, is the standard material for fingerboards on bowed string instruments such as violins, violas, and cellos, due to its exceptional hardness and stability. With a Janka hardness rating of 3,220 lbf and a density of approximately 1.21 g/cm³, ebony provides a firm, unyielding surface that withstands repeated finger pressure and string contact while offering quick note response and a clear, bright timbre.[23][24] Its low porosity and high wear resistance (113 mg/100 revolutions in abrasion tests) minimize indentations and ensure longevity, though its fine grain can feel slick under the fingers.[24][25] Rosewood, derived from Dalbergia species such as Indian rosewood (Dalbergia latifolia), dominates fingerboard construction on fretted instruments like acoustic and classical guitars, valued for its oily composition and resonant qualities. This wood exhibits a density of 0.81 g/cm³ and moderate hardness (cross-grain values around 9.1 kN), contributing to a warm, balanced tone with enhanced low-end warmth due to higher damping of harmonics compared to ebony.[24][26] The natural oils in rosewood reduce friction, potentially lessening string wear during play, while its open grain absorbs some vibrations for a softer attack.[27] However, sustainability concerns arose with CITES Appendix II listings for most rosewood species in 2017, imposing trade restrictions to combat overharvesting, though exemptions for finished musical instruments were granted in 2019.[28] Maple (Acer spp.), often hard rock maple, is commonly employed for fingerboards on electric guitars and basses, delivering a bright, snappy tone suited to amplified playing. Its lower density of 0.69 g/cm³ and hardness (cross-grain around 7.6 kN) promote faster attack and articulate highs, with reduced damping that preserves harmonic clarity.[24][29] This material's tight grain enhances sustain by efficiently transmitting string vibrations, though it may require periodic oiling to prevent drying in low-humidity environments.[27] In response to wood scarcity and environmental regulations, modern fingerboards increasingly incorporate synthetic and composite alternatives that prioritize dimensional stability and cost-effectiveness. Graphite composites, often reinforced with epoxy, offer superior resistance to humidity fluctuations, maintaining shape without warping—a key advantage over traditional woods in varying climates.[30] These materials exhibit high stiffness and density, akin to ebony, supporting extended sustain while avoiding the acoustic damping of oilier woods.[26] Phenolic resins, composed of paper or fabric impregnated with resin, serve as durable options for budget instruments, providing a hard, ebony-like surface that is inexpensive to produce and resistant to wear, though less tonally warm. Recent innovations as of 2025 include GaiaTone, a durable material made from recycled paper, and Richlite, a paper-resin composite used by manufacturers like Martin Guitars for fingerboards and bridges.[30][31][32] Pau ferro (Machaerium scleroxylon), a sustainable substitute for rosewood, features similar oily texture and reddish hue but with tighter grain for brighter response, bypassing CITES restrictions while approximating rosewood's resonance.[27][33] Material selection for fingerboards hinges on balancing acoustic performance, playability, and practicality. Higher density generally correlates with longer sustain, as denser woods like ebony transmit vibrations more efficiently to the neck, reducing energy loss.[27] Oil content, prominent in rosewoods and pau ferro, lubricates the surface to minimize string abrasion and enhance sliding ease, while damping properties influence tonal warmth—rosewood's moderate absorption yields a fuller, less brittle sound than ebony's precision.[24] Sustainability remains a driving factor, with CITES measures since 2017 accelerating shifts toward composites and alternatives to protect endangered species without compromising instrument quality.[28]Manufacturing Processes
The manufacturing of fingerboards begins with the preparation of raw tonewood, where the wood is dried—typically by kiln-drying for fretted instruments or air-drying for bowed string instruments—and ends are sealed with wax or resin to stabilize moisture content and prevent cracking during processing. Ideal moisture levels for tonewood range from 6% to 9%, with many luthiers targeting 6-8% to match the equilibrium moisture content of typical indoor environments and minimize warping risks. This practice became standardized in 20th-century luthiery as moisture meters enabled precise quality control, ensuring dimensional stability before shaping.[34][25] Shaping involves selecting a blank slightly oversized and planing it to the desired thickness, typically 0.24 to 0.35 inches (6 to 9 mm) for guitar fingerboards, depending on the instrument scale and neck design. The blank is then radiused if needed and trimmed to length, often using hand planes or CNC routers for precision in modern production. Ebony, prized for its density, facilitates smooth planing due to its fine grain.[35][36] Attachment to the neck follows, with the fingerboard glued directly to the neck's top surface after scuffing both with 80-120 grit sandpaper for optimal adhesion. Traditional acoustic and violin fingerboards use hide glue for its reversibility and acoustic transparency, while modern electric and steel-string guitars often employ PVA glues like Titebond for strength or epoxy for enhanced stability against humidity changes. Locating pins or staples (3/32 to 1/8 inch above the surface) are inserted to align the fingerboard precisely during clamping, preventing slippage. For set-neck designs, a mortise-and-tenon joint may integrate the heel before gluing. Clamping ensures even pressure, with the assembly cured under controlled conditions to avoid stress.[35][37] Inlay installation for position markers occurs after shaping but before final attachment, involving precise routing of cavities using a Dremel tool or CNC for complex designs. Slots are cut slightly deeper than the inlay thickness (e.g., 0.052 inches for a 0.049-inch abalone piece), and the inlay—often mother-of-pearl, abalone, or plastic—is fitted and secured with epoxy, CA glue, or fish glue mixed with black pigment for binding. Excess material is leveled flush with the surface using files and high-grit abrasives like 12,000-grit Micro-Mesh, ensuring a seamless finish.[38] Fret slots are sawn perpendicular to the centerline after inlay work, with depths set to accommodate the fret tang, typically 0.060 to 0.075 inches (1.52 to 1.90 mm) using a depth gauge for verification. A specialized fret saw or miter box guides the cut to a uniform width of about 0.023 inches, avoiding over-penetration that could weaken the board.[39][40] Finishing protects the fingerboard and enhances playability, with unfinished rosewood boards oiled using formulations like linseed and mineral oil blends to prevent drying and cracking while restoring smoothness. Application involves wiping on sparingly with a lint-free cloth, buffing after absorption, and allowing 24 hours to cure; lemon oil serves a similar purpose for periodic maintenance. Lacquering is avoided on most fingerboards to preserve tonal resonance, though clear coats may appear on some synthetic or sealed variants. Post-finishing, the board undergoes final inspection for flatness and alignment before integration.[41][42]Frets and Fretless Designs
Fret Types and Materials
Frets on fingerboards are typically raised metal bars that divide the scale length to facilitate precise intonation in fretted string instruments. The most common type is the bar fret, consisting of a tang portion that fits into a slot cut across the fingerboard and a crown that protrudes above the surface for string contact.[43] For guitars, these bar frets usually have a crown height ranging from 0.040 to 0.055 inches, providing a balance between playability and durability.[44] Variations exist across instruments; ukuleles often feature similar bar frets but incorporate dot inlays as position markers for easier navigation, typically at frets 5, 7, 10, and 12.[45] In vintage banjos, T-style frets—characterized by a T-shaped cross-section—were used for enhanced stability and tone in early 20th-century designs.[46] The primary material for frets is nickel-silver alloy, composed of approximately 65% copper, 18% nickel, and 17% zinc, which offers corrosion resistance suitable for regular use while producing a warm tone.[47] Stainless steel frets, introduced in custom builds during the late 20th century and popularized in the early 2000s, provide superior durability for heavy playing due to their hardness and resistance to wear, though they can feel slicker under the fingers.[48] For high-end instruments, gold-colored frets made from copper alloys like C425 are employed for aesthetic appeal and added corrosion resistance, often without actual gold plating to maintain longevity.[49] Frets ensure accurate intonation by dividing the scale length into equal semitone intervals based on the 12th root of 2 ratio, approximately 1.05946, which corresponds to the frequency multiplication for each half step. The position of the nth fret from the nut is calculated as , where is the scale length and is the fret number; this formula approximates ideal string behavior under equal temperament.[50] This geometric progression allows consistent pitch across the fingerboard when strings are pressed against the frets. Fret wear occurs primarily from friction with strings, exacerbated by heavier string gauges that increase pressure and flattening over time, leading to intonation issues and buzzing.[51] Replacement is typically required every 5-10 years for intensive play, though this varies with usage and maintenance.[52] In contrast, fretless fingerboards omit these elements entirely, relying on the player's skill for pitch control.Fretless Fingerboards
Fretless fingerboards feature a smooth, uninterrupted surface that allows strings to vibrate freely against the wood, typically ebony or rosewood, without metal frets to divide the scale. To aid players in locating approximate note positions, these fingerboards often include inlaid markers such as side dots or lines at standard intervals, providing visual references without constraining pitch. On electric basses, a protective coating like epoxy resin is commonly applied to the fingerboard to enhance durability, facilitate smooth finger sliding, and preserve the wood from wear caused by roundwound strings, a technique popularized in the late 20th century.[53][3] Intonation on fretless fingerboards relies heavily on the player's ear and muscle memory, as there are no frets to ensure precise pitch, requiring constant adjustment to achieve accurate notes in equal temperament or other systems. Visual markers assist beginners in approximating positions, but experienced players develop intuitive control through practice, often training by mimicking vocal inflections or using tuners for feedback. This design enables microtonal expression, such as the subtle pitch bends for blue notes in jazz bass lines, allowing deviations from standard tuning for expressive nuance.[54][55] The primary advantages of fretless fingerboards include the ability to produce continuous pitch variation, facilitating smooth glissandi and portamento effects that enhance melodic fluidity, in contrast to the discrete pitches enforced by frets. The direct contact between the strings and the wooden surface contributes to a warmer, more organic tone with reduced high-frequency emphasis, as the absence of metal frets avoids the brighter attack and sustain associated with fretted designs. This results in a vocal-like quality, particularly suited to genres emphasizing expression over rhythmic precision.[3][56] Historically, fretless fingerboards have been standard on bowed string instruments like the violin and double bass since their development in the 16th century, evolving from earlier medieval bowed instruments such as the rebec and vielle, many of which were fretless or featured movable tied frets to allow variable intonation suited to the expressive demands of medieval music. While upright double basses maintained this fretless tradition through the centuries for arco and pizzicato playing, the fretless electric bass emerged in the mid-20th century and gained prominence in the 1970s through jazz fusion pioneer Jaco Pastorius, who modified a Fender Jazz Bass by removing its frets, filling the slots, and applying epoxy, thereby expanding its use in modern genres.[53]Design Parameters
Radius and Contour
The radius of a fingerboard refers to the curvature of its surface across the width of the neck, measured as the radius of an imaginary circle whose arc approximates the fingerboard's curve. This parameter varies significantly by instrument type. On fretted plucked instruments like guitars, a smaller radius indicates a more pronounced curve, while a larger radius results in a flatter profile. This curvature is essential for aligning the frets and strings ergonomically. On bowed string instruments like violins, the radius is tighter (typically around 42 mm) to match the arched bridge and allow the bow to contact individual strings.[57][58] For guitar fingerboards, the radius is quantified using the sagitta formula, which calculates the height (h) of the arc's deviation from a straight line across the fingerboard's width (w):where r is the radius and the approximation holds for small angles typical in fingerboard design. This formula allows luthiers to determine the precise curvature needed during manufacturing, ensuring consistent playability; for instance, it relates the radius to the fingerboard's width, which influences the overall feel when combined with thickness.[59] Common radii on guitars vary by instrument era and style, with vintage electric guitars often featuring a 7.25-inch radius for a rounded contour suited to rhythm playing, while modern designs favor flatter profiles around 16 inches to accommodate faster techniques. A compound radius, which gradually flattens from the nut to the bridge (e.g., 10 to 16 inches), combines these benefits by easing barre chords near the nut and enabling low-action bends higher up the neck without string buzz. Steeper radii (smaller values) enhance comfort for chording by better matching the natural arch of the fretting hand, whereas flatter radii support solos and bending by allowing strings to lie closer to the board.[60][61][62] The standardization of radiused fingerboards emerged in the 1950s with the rise of electric guitars, as manufacturers like Fender adopted curved profiles around 7.25 inches to improve ergonomic comfort and intonation over flat boards used in earlier acoustics. This innovation addressed the demands of amplified playing styles, prioritizing hand position and string tension balance.[61] For bowed instruments, the contour is designed to align with the bridge arch, with violin fingerboards typically featuring a radius of about 42 mm across the width, ensuring proper string height differences between bass and treble sides.[57]
