How the Tailpiece Dances with the Violin: Insights into Tailpiece Tuning
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Dances with the Violin: Insights into Tailpiece Tuning T.B (Ted) White VSA Meeting - Baltimore November 2013
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How the Tailpiece Dances with the Violin: Insights into Tailpiece Tuning. T.B (Ted) White VSA Meeting - Baltimore November 2013. What Is The Ideal Tonal Adjustor?. No modification of instrument required Inexpensive Does not require adding parts Adds flexibility to the setup process - PowerPoint PPT Presentation
Transcript of How the Tailpiece Dances with the Violin: Insights into Tailpiece Tuning
The Tailpiece as a Non-Radiating Filter for Violin Family Instruments
How the Tailpiece Dances with the Violin: Insights into Tailpiece TuningT.B (Ted) WhiteVSA Meeting - BaltimoreNovember 2013What Is The Ideal Tonal Adjustor?No modification of instrument requiredInexpensiveDoes not require adding partsAdds flexibility to the setup processDoes not require string take-downDesirable Possible EffectsTonal quality improvementPlayability improvementWolf note managementSinks and SourcesThink of energy flowing around in the instrument from various sources into sinksBow into string into bridge into instrument bodyBut what about the other way around?And what about the tailpiece and nut?Helmholtz Motion of a String
Bridge ReflectionNut ReflectionTailpieceInstrument BodyTailpiecesTailpieces are easy to work withThey are attached directly to the stringsLikely to affect bridge mobilityLikely to act as part of a mass damperCertain modes of the afterlength/tailpiece/tailgut system may be close to the wolfTonal Changes Are Known To Occur With:Afterlength adjustmentTailgut adjustment or changeChanging tailpiecesWeighting tailpiecesCarving or lightening tailpiecesPossible Theoretical BasisMass resonator as a rigid mass and sprung suspensionDamping via flexure of the tailpieceSympathetic vibration of after-lengths (Tuning to 1/6th rule etc.) Radiation dampingRigid Body Mass Resonator FactorsTailpiece massTailpiece mass distributionElasticity and tension of string after-lengths and tailgutLengths of afterlengths and tailgutOther mechanical properties of strings and tailgutSimple Mass and Spring Systems
Flexural Damping FactorsWood properties of the tailpieceSectional properties of the tailpiece shapeMass distributionBoundary conditions at supportsIdentified Tailpiece ModesStough, 1996, CASJ 3, Series II showed for violins:3 swing modes below open G (roll)2 rotational modesAbout a vertical axis (yaw)About a horizontal axis (pitch)E. Fouilhe, et. al. 2011, measured 9 modes for cello both rigid and flexuralAfterlength Tuning FactorsPresumed interval or length ratioLength of tailpiece vs. length of tailgutEffect of silkingEffect of fine tunersEffect of end type loop or ballMute or wolf eliminator massFrequency Response Functions of Nine Cello Tailpieces
Tailgut vs. AfterlengthTailpiece Survey ConclusionsPitch and Yaw modes dominate rigid body modesPitch mode closest to wolf noteTailgut length more important than afterlength in rigid mode resonancesHigher modes highly variableFinite Element Analysis (FEA)Computer analysisAccurate material and structural modelsPossible to predict stress and strainPossible to predict structural acousticsVery useful in designCello Tailpiece Pitch Modes
Cello Tailpiece Yaw Modes
Cello Tailpiece Roll and Translate Modes
Cello Tailpiece Flex Mode
C String After-length Modes
G String After-length Modes
D and A String After-length Modes
What does it all mean?Remember that it is the energy flow between the sinks and sources that mattersA light part can move a lot with out much energyA heavier part will contain more energy for the same movementCello Tailpiece and After-length ModesHow can we use this knowledge?Try various tailpieces, tailguts, etc. and see what worksOr, invent a tailpiece which can permit some adjustment of one or more of the important factorsNew Tailpiece Design GoalsMust be able to adjust pitch and yaw modesMust be able to adjust flexural modesAdjustment must simpleNo requirement for re-tuning or other instrument changesNo increase in tailpiece weightNew Cello Tailpiece Underside
Adjustable MassAdjustable Weight SystemAdjustable Weight SystemViolin with Adjustable Weight Forward
Tailpiece light green
Bridge Admittance greenPitch ModeB1+B1-Violin with Adjustable Weight Midway
Tailpiece blue
Bridge Admittance - RedPitch Mode (splitby B1+)B1+B1-Violin with Adjustable Weight Aft
Tailpiece Horizontal Axis green
Bridge admittance - bluePitchB1+ (splitby Pitch)B1-Violin Bridge Admittance
Weight Forward - blue
Weight Midway - red
Weight Aft - greenHigher ModesUser FeedbackMany makers are now using the new tailpieceFound to be effective at adjusting tone and reducing the wolf noteUsers like the ease of adjustmentHas been compared to soundpost adjustmentConclusionsAny tailpiece affects tone and may also mitigate wolvesAdjusting tailgut length changes toneChanging tailpieces or adding or removing mass will affect toneAn adjustable tailpiece can be a significant tool in tonal adjustment
Practical ApplicationsLearn to play the tailpiecePluck or use a Fuhr tube to vibrate the tailpiece modesListen to the pitchMatching pitch with a wolf note may reduce itThe End (for now!)
Arbutus Fittings 3938 Gilbert Drive, Victoria, BC, Canada, V9C 4B2 [email protected]
This work was supported by a grant from the National Research Council of Canada and the University of Victoria
