Presentation on theme: "Eva Björkner Helsinki University of Technology Laboratory of Acoustics and Audio Signal Processing HUT, Helsinki, Finland KTH – Royal Institute of Technology."— Presentation transcript:
1 Eva BjörknerHelsinki University of Technology Laboratory of Acoustics and Audio Signal ProcessingHUT, Helsinki, FinlandKTH – Royal Institute of TechnologyTMH – Department of Speech, Music and HearingStockholm, Sweden
2 My background: (except being Swedish) MSc in voice/singing coaching (1998)Voice research assistant to Professor Johan SundbergFrom : Teaching singing 75% & research 25%HOARSE 100%Professor Johan Sundberg, at the dept of Speech, Music & Hearing, KTH, Stockholm, Sweden is one of the worlds most well know researchers in the field of analysis of the singing voice production.
4 My research: Analysis of voice production in the singing voice Keywords:voice source characteristicsinverse filteringformant frequenciesthe effect of subglottal pressure variation on the voice sourceAND..The Normalized Amplitude Quotient NAQ (Alku et al. 2002) for what purposes can it be used?
5 from very low to extremely high pitches (Hz) Glottal excitation estimation during singing is very challenging because of the wide ranges between extremes:from very low to extremely high pitches (Hz)from extremely loud to very soft phonations (dB)voice qualities – hypo-/hyper functional etcregisters – differences in vocal fold vibratory patternSpeech: you decidewhen to breathepitchvoice qualityloudnessSinging – the music decides!Entails demand for control ofbreathing behaviourPspitchvoice quality
6 Sound Production Contraction of expiratory muscles The voice sourceThe pulsating air through the glottisContraction of expiratory musclesRise in subglottic air pressureEscape through glottisClosureBernoulli effectelasticity
7 Mask or microphone recordings Flow (Rothenberg mask)AudioTEAC Multi channeldigital recorderOralpressureEGG
8 Inverse filtering of the glottal flow (or sound pressure signal) By eliminating the contributions from the vocal tract, e.g, the formant frequenciesAn acoustic approach to understand vocal fold vibratory patternsthe glottal volume velocity waveformParameterization of the wave form using time-domain methods corresponds to quantifying the glottal flow using certain quotients:Closed Q, Closing QOpen Q, Opening Q,Speed Q, etc
10 NAQ = the normalized amplitude quotient Glottal closing phaseInformation about vocal intensity and phonation type are reflected in the changes of the glottal closing phase.The amplitude-based NAQ has been found to be more robust than the time-based Closing Quotient, because the extraction of NAQ does not involve the problematic time-instant of the glottal opening.Negative peak of the differentiated flowÛp-t-p(MFDR*T0)Alku P, Bäckström T, Vilkman E. (2002)
11 Aim: Better understanding of register function in female singing voice Voice Source Differences Between Registers In Female Musical Theatre Singers Björkner E, Sundberg J, Cleveland T & Stone R. E. accepted for publication in J.VoiceAnalysis: voice source and subglottal pressure Ps characteristics of the chest and head register in the female voice.studied by inverse filteringa sequence of /pae/ syllables sung at constant pitch and decreasing vocal loudness in each register by seven female musical theatre singersten equidistantly spaced Ps values were selected and the relationships between Ps and several parameters were examinedAim: Better understanding of register function in female singing voiceHigh subglottal pressures are known to jeopardizevocal health in both speech and singing
12 => Register differences Means across Clear SamplesGlottogram parametersControl parameter=> Register differences
13 Same pressure = approximately 11 cmH2O Register differences
14 Qclosed - NAQThe lower NAQ values for chest register suggest a more adducted phonation, as compared to head register.
15 NEXT: Male musical theatre singers How NAQ varies with pressure and different pitches (Hz) Articles accepted for publication inthe Journal of Voice:“Voice source differences Between Registers in Female Musical Theatre Singers”Björkner E, Sundberg, Cleveland T & Stone R.E“Throaty Voice Quality: subglottal pressure, voice source, and formant characteristics”Laukkanen A-M, Björkner E & Sundberg JArticle on their way:“NAQ variation with Ps in ClassicallyTrained Baritone Singers”Björkner E, Sundberg J & Alku P“Comparison of two inverse filtering methods for determining NAQ and closing quotient - Voice source characteristics in different phonation types”Lehto L, Airas M, Björkner E, Alku P