Auditory loudness perception and the consumption of popular music between 1980 and 2010 Dong Ho Kwak Auditory loudness perception and the consumption of popular music between 1980 and 2010 Dong Ho Kwak A mini-dissertation submitted in partial fulfilment of the requirements for the degree MMus (Music Technology) Department of Music Faculty of Humanities University of Pretoria Supervisor: Mr Murray de Villiers September 2015 ii Abstract This quantitative study investigates the possible correlation between auditory loudness perception and commercial success in the music industry by measuring and comparing the loudness levels of the top 10 and the bottom 10 singles from the Top 100 Billboard Year End Chart between 1980 and 2010. A total of 140 singles from 1980 and 2010 (with 5 year intervals) were measured in terms of integrated loudness, momentary maximum loudness and loudness range. The variables were measured using the computer software based processing of iZotope Ozone Insight and Waves Loudness Meter (WLM) on Cubase 5 Digital Audio Workstation (DAW) platform. The data were analysed for any observable trend in terms of loudness level, commercial success and consistency between iZotope Ozone Insight and WLM. The analysis clearly showed the steady increase in loudness level over time. Between the top 10 and the bottom 10 singles, there was no statistically significant difference. Therefore the results of this study illustrated that, for the Top 100 Billboard Year End Chart, there is no evidence of any correlation between the perceived loudness and the commercial success (sales). iii Acknowledgements ∙ SABC Media Library: the manager and the staff, for all the trouble they went through to collect the right CD recordings for data collection, and their valuable inputs for this study. ∙ The department of Statistics (University of Pretoria): for very quick replies to all the emails and clear guidance which made the understanding of statistics straightforward. ∙ Murray de Villiers (University of Pretoria): for putting up with all the long emails, text messages and positive advice for this study. ∙ Tarryn Denton: for last minute help and strict guidance, and enthusiasm and interest for this study. ∙ Prof H.H. van der Mescht (University of Pretoria): for the motivation, supervision, support, guidance and proof reading. ∙ Dr C. Panebianco-Warrens: for long and open discussions, knowledgeable advice and guidance, and constructive inputs for this study. ∙ Grace, Hong: for continuous support, inspiration, encouragement, and assistance for data collection. iv Contents Abstract ii Acknowledgement iii List of abbreviations vi Concept clarification vii List of figures viii List of tables x Keywords xi Chapter 1 Introduction 1–1 1.1 Background to the study 1–1 1.2 Aims of the study 1–2 1.3 Research questions 1–3 1.4 Delimitations of the study 1–3 Chapter 2 Literature review 2–1 2.1 Loudness perception 2–1 2.2 Auditory loudness perception and human hearing 2–2 2.3 The progressive loudness escalation 2–7 Chapter 3 Research methodology 3–1 3.1 Research design 3–1 3.2 Music corpus 3–1 3.3 Data collection 3–2 3.4 Data analysis 3–4 Chapter 4 Results and discussion 4–1 4.1 Integrated loudness measurement of the top 10 and the bottom 10 singles 4–1 4.2 Momentary maximum loudness measurement of the top 10 and the bottom 10 singles 4–4 4.3 Comparison of loudness range between the top 10 and the bottom 10 v singles 4–6 4.4 Comparison between iZotope Ozone Insight and WLM measurement plug-ins 4–7 Chapter 5 Conclusions and recommendations 5–1 5.1 The average loudness level trend of the top 10 and the bottom 10 singles 5–1 5.2 Is commercially successful recorded music louder than less successful recorded music between 1980 and 2010, and if so, to what extent? 5–2 5.3 Consistency between the loudness measurement plug-ins, particularly iZotope Ozone Insight and Waves Loudness Meter 5–2 5.4 Answering the main research question: To what extent does the loudness of commercial music recordings affect music sales as reflected by the sales chart position of the popular music industry between 1980 and 2010? 5–3 5.5 Recommendation for further research 5–3 List of sources S–1 Appendix A: Top 10s and Bottom 10s of the Billboard Top 100 Year End Charts: 1980, 1985, 1990, 1995, 2000, 2005 and 2010 A–1 Appendix B: Box plot groups over time A–4 Appendix C: Matched t-test result A–6 Appendix D: Repeated measures with extreme outliers omitted A–9 Appendix E: Repeated measure comparisons A–17 Appendix F: Box plots (notes from the department of Statistic, University of Pretoria) A–21 Appendix G: Results of iZotope Ozone Insight and WLM measurements A–22 vi List of abbreviations AES Audio Engineering Society BLV Between Listener Variability CRC Communications Research Centre Canada DAW Digital Audio Workstation dB Decibel dBFS Decibels Full Scale EBU European Broadcasting Union EBU R128 European Broadcasting Union Recommendation 128 GLM General Linear Model ISO International Organization for Standardization ITU International Telecommunications Union ITU-R BS.1770 International Telecommunications Union-Radiocommunication Broadcasting Service (Sound) 1770 LU Loudness Unit LUFS Loudness Unit Full Scale RLB Revised Low-frequency B-curve SABC South African Broadcasting Corporation SAS Statistical Analysis Software SPL Sound Pressure Level SRG Special Rapporteur Group WLM Waves Loudness Meter WLV Within Listener Variability vii Concept clarification Decibel (dB) Decibel means tenth of a Bell which is a telephone communication measurement unit (named after the inventor, Alexander Bell). The unit is used to measure Sound Pressure Level (SPL). (Huber 2010: 58.) High Pass Filters (HPF) HPF attenuates the lower frequencies of the audible spectrum and allows specific frequency bandwidths to pass at full level (Huber 2010:480). Leq Leq is defined as equivalent continuous sound level (Lund 2011b:9). It is the Sound Pressure Level (SPL) in decibel (dB) which indicates the average of the total sound energy over a specific period of time (Bernard 1987:2). Root Mean Square (RMS) The human ear perceives loudness in relation to the average volume level rather than peak level. In order to visually represent the estimated auditory loudness, the mathematical Root Mean Square function is applied to show the average volume level of sound. (Izhaki 2008:95–96.) Sound Pressure Level (SPL) It is the acoustic sound pressure within a limited area. SPL is directly related to the auditory loudness: when SPL increases, the loudness level also increases. (Huber 2010: 59.) Weighting (filters) It is utilised, when measuring SPL, to imitate the natural frequency response of human hearing as illustrated in the Equal-loudness contour. There are different weighting curves employed on SPL meters. dBA is one of the most common weighting curves applied when measuring SPL. This curve represents the response of human hearing at 40 phons according to the Equal-loudness contour. (Stark 2005:73–74.) viii List of figures Figure 1 Human hearing response according to the ISO 226:2003 Standard Equal- loudness contour (ISO:2003) 2–2 Figure 2 Frequency response of A, B, C, D, M and RLB weighting filters (Skovenborg & Nielsen 2004:7) 2–3 Figure 3 Inter-individual variability in terms of frequency (Hz) and intensity (dB) in persons younger than 35 years (Von Wedel, Meister & Walger 2000:191) 2–4 Figure 4 Inter-individual variability in terms of frequency (Hz) and intensity (dB) in persons older than 45 years (Von Wedel, Meister & Walger 2000:190) 2–5 Figure 5 Box plot of combined integrated loudness measurements with iZotope Ozone Insight grouped by year and categorized by chart group (data.sta 10v* 140c). LoudnessInsight indicates the loudness level measured by iZotope Ozone Insight 4–1 Figure 6 Box plot of combined integrated loudness measurements with WLM grouped by year and categorized by chart group (data.sta 10v* 140c). LoudnessWLM indicates the loudness level measured by WLM 4–3 Figure 7 Box plot of momentary maximum loudness measurements with iZotope Ozone Insight grouped by year and categorized by chart group (data.sta 10v* 140c). MomentaryMaxI indicates the loudness level measured by iZotope Ozone Insight 4–4 Figure 8 Box plot of momentary maximum loudness measurements with WLM grouped by year and categorized by chart group (data.sta 10v* 140c). MomentaryMaxW indicates the loudness level measured by WLM 4–5 Figure 9 Box plot of loudness range measurements with iZotope Ozone Insight grouped by year and categorized by chart group (data.sta 10v* 140c). RangeInsight indicates the loudness range level measured by iZotope Ozone Insight 4–6 Figure 10 Box plot of loudness range measurements with WLM grouped by year and categorized by chart group (data.sta 10v* 140c). RangeWLM indicates the loudness range level measured by WLM 4–7 ix Figure 11 Box and whisker plot for LoudnessInsight versus LoudnessWLM. The two variables indicate the mean difference between iZotope Ozone Insight and WLM 4–8 x List of tables Table 1 iZotope Ozone Insight and WLM default measurement settings 3–3 Table 2 Summary of LoudnessInsight GLM results 4–2 Table 3 T-test results for dependent samples of iZotope Ozone Insight and WLM. The two mean values compared regardless of chart position or time period. The extreme outliers were omitted from the analysis 4–8 Table 4 The mean value of integrated loudness measurement of the top 10 and bottom 10 singles each year 5–1 xi Keywords Auditory loudness perception Billboard Top 100 Year End Charts 1990–2010 Consumption of popular music EBU R128 recommendation ITU-R BS.1770 iZotope Ozone Insight Loudness measurement Loudness War Music consumption Progressive loudness escalation Waves Loudness Meter 1-1 Chapter 1 Introduction 1.1 Background to the study In a competitive music recording market, artists and record companies strive to differentiate themselves from their competitors with each new album release, especially in the popular music (which refers to music that has wide appeal) genre (Middleton 2001:128–129).