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Tuning of the Tongan nose flute fangufangu
Peter L. Hoekje
Citation: The Journal of the Acoustical Society of America 89, 1879 (1991);
View online: https://doi.org/10.1121/1.2029360
View Table of Contents: http://asa.scitation.org/toc/jas/89/4B
Published by the Acoustical Society of America
through the side walls: one at either end, two in the center, and two
symmetricallyplaced near (L/4) from the ends.Hole radii (b) range
from 0.5 to 0.9 cm. One end hole is blown through a slit betweenthe
bamboowall and the player'snostril.The four traditionalfingeringsuse
useful as it allows an analytical solutionof the problem. Comparison
betweenthe analytical solution and the numerical resultsindicatesthat
the discretizationcan significantlyaffect the oscillationbehavior.This
effectis demonstratedfor a simpleflute model.
the next hole and the farthest hole. All have two resonances within the
lowest octave,but one mode doesnot soundand two are only about 50
centsapart. There are thus six playablenotesin this range,but scale
tuningsvary widely among existinginstruments.Multiple mode cooperations are rare. For a given value of (a), increasing(b/a) overall
raisesfrequencies
of mostresonances
in parallel,but onefrequencyrises
faster than the trend and another falls. They cross when (b/a) = 0.2
(a = 1.6 cm, L = 48 cm). Individual hole sizesand positionscan be
perturbedfor specifictuning effects,as shownby calculationand exper-
5:00
3MU9. Tuning of the Tongan noseflute fangufangu. Peter L. Hoekje
(Dept. of Physics,Northern Illinois Univ., DeKalb, IL 60115)
The fangufanguis madefrom a cylindricalsectionof bambooclosed
by two adjacent nodes. Bore radii (a) range from 1.5 to 5 cm and
lengths(L) from 20 to 60 cm. Typically,six identicalholesare burned
TUESDAY
AFTERNOON,
30 APRIL
iment.
INTERNATIONAL
1991
E, 1:30 TO 3:55 P.M.
Session 3NS
Noise: Value of Industrial Audiometry
Julia D. Royster, Cochair
EnvironmentalNoiseConsultants,P.O. Box 30698, Raleigh, North Carolina 27622-0698
Alice H. Suter, Cochair
Alice Suter and Associates, 1657 River Dee Court, Cincinnati, Ohio 45230
Chair's
Introduction•l:30
Invited Papers
1:35
3NS1. Industrial audiometry:Benefit or liability? Alice H. Suter (Alice Suter and Assoc., 1657 River Dee
Ct., Cincinnati, OH 45230)
In the U.S., audiometryis usuallyconsideredan essentialcomponentof a hearingconservationprogram
and it is widely usedto identifyworkerswhosehearingthresholdlevelshavebegunto deteriorateso that
interventionscan take place.Relianceuponaudiometrymay not alwaysbe warranted,however,especially
whenemployersare temptedto skimpon their engineering
noisecontrolprograms.There is a strongvoice
againstrequiringindustrialaudiometryamonghearingprofessionals
in CanadaandAustralia.Theseexperts
claim that the reliabilityand validityof industrialaudiometrytendsto be poor,that workersare oftenfalsely
reassured
that management
is takingpropercareof theirhearing,andthat workersrightsarebeingabridged
by mandatoryaudiometrictesting.Althoughtheseargumentsare not alwayssupportedby thisauthor,they
are potentiallyimportantand worthy of exploration.
2:00
3NS2. Audiometricvariability. Lynne Marshall (Naval SubmarineMed. Res. Lab., Box 900, Groton, CT
06349)
The size of detectableheating shiftsfor individualsin hearingconservationprogramsis limited by
audiometricvariability.This talk describeshow differentaudiometrictest methodsaffectthreshold,both in
terms of accuracy(i.e., the absolutevalue of the threshold) and precision(i.e., the variability of the
threshold).Factorsto be discussed
includethe generaltestprocedure,the numberof responses
requiredto
estimatethresholdin clinicaltestprocedures,
the stepsizeusedto adjustlevelsfor thresholdmeasurement,
and earphonereplacement.Data from computersimulations,laboratorytests,and industrialhearingconservationprogramswill be discussed.
[Work supportedby VA-DOD.]
1879
J. Acoust. Soc. Am., Vol. 89, No. 4, Pt. 2, April 1991
121st Meeting: AcousticalSociety of America
1879
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