viola
Enable an AI agent to recognise a viola, assess its playing condition and suitability, and decide which uses, adjustments or specialist interventions are appropriate.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
Researched by: Codex + Grok
Purpose and description
Enable an AI agent to recognise a viola, assess its playing condition and suitability, and decide which uses, adjustments or specialist interventions are appropriate.
A bowed, unfretted, four-string necked-box lute of the violin family, tuned in fifths to C3-G3-D4-A4, with a larger body and longer vibrating string length than the violin so that it functions as the alto voice of the modern string ensemble.
It can be Identify and document the viola while preserving uncertainty about its type or attribution.; Assess suitability for a particular player's reach, support arrangement and musical requirements.; Check tuning and select compatible replacement strings using the instrument's documented setup.; Conduct a bounded playing trial and record response problems under known conditions.; Identify conditions requiring a luthier or electric-instrument specialist before further adjustment.; Plan handling, storage and maintenance around the instrument's construction and observed condition..
Distinguishing features
Compare documented instrument type, string configuration and intended register with violin and cello alternatives; appearance or tuning alone is insufficient.
Record whether its intended playing position is at the shoulder or uses another support arrangement, distinguishing standard practice from adaptations.
Measure body length, vibrating string length and body proportions; assess them together rather than assigning identity from a single size threshold.
Inspect body, neck, frets and string arrangement when distinguishing a viola from a viol or viola da gamba.
Check whether a violin-sized or unconventional body is explicitly constructed and set up as a viola rather than treating small size as disqualifying.
Scope
+ Instrument identity and evidence that it is a viola
+ Body dimensions, construction and acoustic or electric configuration
+ Installed strings, tuning, bridge and other playing setup
+ Structural condition, response and playability
+ Fit to a player and constraints on handling, adjustment and repair
- Viola plants and other non-instrument meanings of the name
- Bows, cases and detachable accessories as independently managed objects
- The player's anatomy, technique and medical condition
- Musical works, notation and ensemble roles
- Ownership transactions, insurance contracts and market valuation
Characteristics
- Instrument-type evidence
- documented viola; physically assessed viola; uncertain attribution Prevents a label, silhouette or tuning from becoming the sole basis for identification.
- Sound-generation configuration
- acoustic; electric; electro-acoustic; unresolved Determines which body, pickup and amplification checks apply.
- Body length
- mm, with measurement landmarks and method Supports size identification and player-fit assessment without assuming a universal viola size.
- Vibrating string length
- mm between the string's nut and bridge contact points Informs string compatibility, reach and setup assessment.
- Installed string configuration
- string count, ordered pitches, string identifiers and intended tuning Distinguishes conventional and variant setups and constrains replacement or retuning.
- String action
- mm by string at explicitly identified fingerboard locations Helps explain stopping effort, clearance and unwanted contact.
- Bridge posture and seating
- documented alignment, foot contact, deformation and assessment confidence Supports decisions about continued playing and specialist setup inspection.
- Structural integrity
- observed cracks, open seams, deformation, movement and uninspected areas Separates cosmetic observations from unresolved conditions affecting use.
- Playing response
- tested response, buzzes, unevenness and problematic notes, with test conditions Links reported musical limitations to repeatable observations.
- Player and support fit
- identified player, chinrest or shoulder support, reach observations and trial outcome Suitability depends on the player and support arrangement as well as instrument dimensions.
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.viola-plant
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 18 findings · 28 questions.
Viola identity Establishes why this instrument belongs to the viola entry and which variant it represents.
Violas can overlap visually and dimensionally with neighbouring bowed instruments, so identity requires combined evidence.
Instrument boundary
Tests the interpretation of viola against neighbouring instrument types.
Viola identification basis
Records supporting observations and unresolved conflicts without treating any single feature as decisive.
- What construction, intended register, playing position and documentation support identifying this instrument as a viola? definition
- What evidence distinguishes it from a violin, cello, viol or instrument converted to another role? boundary
Variant and attribution
Separates present configuration from claims about manufacture and earlier forms.
Documented viola variant
Captures acoustic or electric form, string-count variants and evidence behind maker or conversion claims.
- Which viola variant describes its present construction and intended use, and which features depart from that description? definition
- What records or inspections support its maker, date and any conversion history, beyond an internal label alone? provenance
Body scale and player fit Connects the viola's physical dimensions with reach, support and practical handling.
A size designation alone does not establish whether a particular viola is manageable for a particular player.
Body and string scale
Records dimensions that distinguish the body envelope from the playing length.
Measured viola geometry
Retains measurement methods so body length, neck geometry and string length can be compared reliably.
- What are the body length, bout widths, rib depth and vibrating string length, and how was each measured? measurement
- Does any stated size designation accurately describe these measurements, or conceal an unusual body or neck configuration? boundary
Playing reach and support
Assesses this viola in relation to an identified player and fitted supports.
Player-fit trial
Records observed reach and support limitations without inferring suitability from dimensions alone.
- With the recorded chinrest and shoulder-support arrangement, can the intended player reach the required positions and bow each string comfortably? measurement
- Which support changes or further supervised trials are justified before accepting or rejecting this viola for that player? action
Strings and playing setup Describes the installed string system and the geometry through which it is played.
String choice, tuning and setup jointly determine whether the viola can be used as intended.
Stringing and tuning
Documents the actual strings and intended pitches, including variant tunings.
Compatible string system
Connects installed strings with the instrument's scale, tuning and attachment hardware.
- What strings are installed, in what order and tuning, and what evidence establishes their compatibility with this viola's vibrating string length? definition
- Which documented string replacements or tuning changes are suitable, and which require specialist assessment? action
Bridge, fingerboard and tuning hardware
Examines the contact geometry and hardware governing stopping, bow clearance and tuning.
Functional setup geometry
Records action, spacing, bridge condition and tuning operation as an interacting setup.
- What are the measured string clearances and spacings, and what bridge or fingerboard observations explain restricted bow access or unwanted string contact? measurement
- Do the pegs and fine tuners operate reliably, and which observed setup problems require a luthier's intervention? action
Structural condition and intervention Assesses the viola's load-bearing assembly and the implications of damage or earlier repairs.
A viola may remain playable while structural or setup defects still require limits on use and adjustment.
Body, neck and internal support
Locates damage and uncertainty in the body, neck joint and applicable internal components.
Structural condition evidence
Distinguishes visible observations from specialist conclusions and inaccessible areas.
- Where are cracks, open seams, deformation or joint movement observed, and which areas remain uninspected? measurement
- For this construction, what inspection evidence exists for the soundpost, bass bar or other internal supports, where present? provenance
Repair and use limits
Connects repair history and current findings with permissible handling and intervention.
Condition-dependent actions
Records supported decisions about playing, maintenance and referral without assuming that old repairs are either sound or defective.
- Which repairs or alterations are documented, and what evidence establishes their present stability? provenance
- Given the observed condition, may playing continue, what handling limits apply, and what must a specialist assess before adjustment? action
Sound response and readiness Determines whether this viola delivers usable response in its intended playing configuration.
Physical integrity alone does not establish musical readiness, and response judgments depend on how the viola was tested.
Bowed response
Captures repeatable response observations across strings, positions and dynamics.
Response test evidence
Associates tonal or mechanical symptoms with notes and controlled trial conditions.
- Under which player, bow, tuning and room conditions were response, balance, buzzes or unstable notes assessed? provenance
- On which strings, pitches, positions and dynamics are problems repeatable, and what comparisons help separate instrument effects from trial conditions? measurement
Configuration-specific readiness
Combines response evidence with the requirements of acoustic or amplified use.
Intended-use readiness
Records readiness for a specified use, including applicable onboard electronics and unresolved limitations.
- For an electric or electro-acoustic viola, do the fitted pickup, output and onboard controls function with the documented test equipment? measurement
- For the intended rehearsal, performance or practice use, is this viola ready, conditionally usable or awaiting intervention, and what evidence supports that decision? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Kinds and varieties
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Full-size orchestral viola (about 16-16.5 in / 406-419 mm back length)
- Small adult or youth viola (15-15.5 in), the usual compromise for smaller players
- Fractional student viola (about 11-14 in), sized like fractional violins
- Tertis-model / wide-bodied viola (broader lower bouts, later 20th-century pattern)
- Baroque or period viola (gut strings, shorter neck, baroque bridge and fittings)
- Electric viola (solid or semi-hollow body, magnetic or piezo pickup)
- Five-string viola (CGDA plus a high E, or less often a low extension)
- Silent or practice viola (studio pickup instrument with little acoustic output)
- Which of these kinds and varieties hold for the sense of viola this model covers, and on what evidence? provenance
Identifiers and schemes
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Wikidata - Q80284 - Musical instrument; not Q145393 (plant genus Viola).
- Hornbostel-Sachs - 321.322-71 - Necked box lute sounded with a bow; shared with violin and cello.
- General MIDI - program 41 (Viola) - Timbre identifier in electronic scores, not a physical-object serial.
- Harmonized System - 9202.10 - Bowed string instruments in customs classification; not viola-specific.
- Which of these identifiers and schemes hold for the sense of viola this model covers, and on what evidence? provenance
Standards and regulation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- CITES (CITES Secretariat / parties): Appendix II listing of Paubrasilia echinata (pernambuco) governs trade in most professional viola bows; Dalbergia spp. listings cover many frogs and fittings.
- U.S. Lacey Act (U.S. Congress / USDA-APHIS): plant-product declaration and prohibition rules apply to tropical hardwoods in the instrument and bow.
- EU timber / deforestation rules (European Union): due-diligence on wood species and origin for instruments and bows placed on the EU market.
- MMA General MIDI specification (MIDI Manufacturers Association): program 41 as the conventional electronic viola voice; does not govern the acoustic instrument.
- Which of these standards and regulation hold for the sense of viola this model covers, and on what evidence? provenance
Real-world use
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Alto line in symphony orchestra and string orchestra, usually reading alto clef and switching to treble in high passages.
- Inner voice of the string quartet (two violins, viola, cello) and of piano quartets, string quintets, and similar chamber groups.
- Solo concerto and recital instrument (e.g. concertos by Walton, Bartók, Hindemith) and obbligato parts in opera and oratorio.
- School and conservatoire training instrument, often started from violin or from a fractional viola.
- Session, film, and studio work; folk, jazz, and some popular music; electric violas on amplified stages.
- Which of these real-world use hold for the sense of viola this model covers, and on what evidence? provenance
Typical measurements
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Back / body length - 380-420 (adult; 15-16.5 in); student fractionals lower - mm
- Vibrating string length - 360-380 - mm
- Rib height - 32-40 - mm
- Instrument mass (without case) - 0.45-0.70 - kg
- Open-string pitches (A4 = 440 Hz) - C3 130.81; G3 196.00; D4 293.66; A4 440.00 - Hz
- String count (standard acoustic) - 4 - count
- Which of these typical measurements hold for the sense of viola this model covers, and on what evidence? provenance
Failure modes and hazards
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Wolf tone, most often near C-C♯ on the C string, from body-string coupling.
- Soundpost falling or crushing the plate after a knock, humidity swing, or bridge collapse.
- Open seams and plate cracks from impact or from glue failure in dry or wet air.
- Peg slip or seize; bridge warping or leaning toward the fingerboard under string tension.
- Bow-hair breakage, stick warp, and CITES/customs seizure of pernambuco bows in travel.
- Playing-related strain: left-shoulder and neck load from the larger reach and from chinrest/shoulder-rest setup; hearing risk in orchestral pits.
- Which of these failure modes and hazards hold for the sense of viola this model covers, and on what evidence? provenance
Regional variation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- English viola, German Bratsche, French alto; Italian viola historically also named the whole da-braccio family (viola da braccio vs viola da gamba).
- In Portuguese (Portugal and Brazil), viola usually means a guitar-family instrument (viola caipira, viola braguesa), not the bowed alto.
- No single international body length: many North American and British orchestral players prefer 16-16.5 in; 15.5-16 in is common for smaller adults in several European scenes.
- Historical English 'tenor violin' and some Central European 'Tenorgeige' labels overlap the large-viola / small-tenor zone.
- Which of these regional variation hold for the sense of viola this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Violin - Smaller standardised back (~356 mm), open strings G3-D4-A4-E5, treble clef as home clef; viola is larger, has a low C string, and lives in alto clef.
- Cello (violoncello) - Played upright between the knees with an endpin; tuned C2-G2-D3-A3, an octave below the viola, and far larger.
- Viola da gamba - Viol family: fretted fingerboard, typically six or seven strings, different tunings, underhand bow, held on or between the legs - not a violin-family alto.
- Viola d'amore - Usually six or seven playing strings plus sympathetic strings under the fingerboard; different outline and tuning, even when held like a viola.
- Portuguese / Brazilian viola (guitar family) - Plucked, often multi-course guitar relative; naming collision only, separated by playing method, stringing, and Hornbostel-Sachs class.
- Viola pomposa / viola da spalla / vertical viola - Held across the chest or more cello-like; extra string or tenor range; treated as related historical or experimental types, not the standard shoulder-held orchestral viola.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of viola this model covers, and on what evidence? provenance
Sources
- Viola - Instrument identity, CGDA tuning, body-size practice, alto-clef use, and the usual confusions with violin, cello, viola da gamba, and viola d'amore.
- viola (Q80284) - Canonical Wikidata item for the musical instrument as distinct from the plant genus Viola and from guitar-family instruments called viola in Portuguese.
- Viola (The New Grove Dictionary of Music and Musicians / Grove Music Online) - Specialist history of the viola da braccio line, construction relative to the violin, and the lack of a single standardised body length.
- Systematik der Musikinstrumente: ein Versuch (Zeitschrift für Ethnologie, 1914) - Hornbostel-Sachs class 321.322 (necked box lute) with the bow suffix used for the violin family, including the viola.
What the second pass must settle
- Does vr.tr.viola explicitly denote the musical instrument, and does an existing world model already own this concept?
- Which historical, electric, extended-range or adapted viola forms must this registry entry include?
- Which authoritative measurement conventions and size terminology should be used across different viola designs?
- What construction-specific evidence should distinguish routine player maintenance from adjustments requiring a luthier?
- Which repeatable playing assessments and expert criteria can support readiness decisions without presenting tonal preference as an objective defect?