Principal component analysis in determining the best setup for acoustic measurements in sound control rooms

Opisan je postupak mjerenja akustičke kvalitete u tonskim režijama, s ciljem utvrđivanja postavki koje daju najtočnije rezultate. Napravljena su mjerenja impulsnih odziva šest tonskih režija. Mjerenja su obavljena sukladno normi ISO3382. U svim tonskim režijama je upotrijebljena ista metoda, ali su mijenjani uvjeti mjerenja. U prvom slučaju korišteni su ugrađeni monitorski zvučnici. U drugom slučaju je korišten neusmjereni zvučni izvor. Neusmjereni mikrofon i umjetna glava su korišteni kao prijemnici. Oni su smješteni na optimalno mjesto za slušanje. Analiza glavnih komponenata je korištena za određivanje najtočnijih rezultata dobivenih uz različite uvjete mjerenja. Na taj način su dobiveni uvjeti mjerenja koji najbolje odgovaraju vrijednostima subjektivnih ocjena tonskih režija. Ti rezultati će biti korišteni za računanje korelacije između izmjerenih objektivnih i ocijenjenih subjektivnih parametara.Measuring process of acoustic quality parameters in sound control room in order to determine the best setup is described. Measurements of six sound control rooms impulse response have been made. The measurements are executed in accordance with the standard ISO3382. In all sound control rooms the same measurement method is used, but the measurement setups are changed. In the first scenario built-in monitor loudspeakers were used. In the second scenario, omnidirectional sound source was used. Omnidirectional measuring microphone and an artificial head were used as receivers. They were placed at the optimal listening position. Principal components analysis method is used to get the most accurate result from measured data obtained under different scenarios and measuring setups. Hence, the measuring conditions and setups which determine the value of subjective assessments of the sound control room are obtained. The results shall be used to calculate correlation between objective measurements and subjective assessments

Correlation between objective and subjective acoustic quality parameters of professional sound control rooms

Brojne provedene analize ne daju jedinstveni odgovor na pitanje ocjene akustičke kvalitete tonskih režija, budući da nisu uvijek uzete u obzir sve karakteristike specifične za tonske režije. U procesu opisanom u ovom radu sve su specifične karakteristike uzete u obzir. Reprodukcija zvuka je provedena visokokvalitetnom profesionalnom opremom. Promatrano je točno određeno optimalno područje za slušanje. Optimalna tonska režija mora omogućiti reprodukciju zvuka sa svim njegovim karakteristikama, a karakteristike samog prostora ne smiju utjecati niti mijenjati karakteristiku reproduciranog zvuka. Združena analiza parametara je korištena za procjenu utjecaja vrijednosti objektivnih parametara akustičke kvalitete na subjektivnu procjenu. Ova moderna statistička metoda pokazuje ovisnost jednog subjektivnog parametra akustičke kvalitete o više objektivnih parametara. Taj princip bolje određuje stvarne uvjete, u kojima je svaka subjektivna ocjena složeno zavisna o više objektivnih parametara akustičke kvalitete tonskih režija.Various studies performed so far have not provided unique answers to the acoustic quality evaluation of the sound control rooms, as no influence of specific features of the respective sound control room have been taken into account. In a process described in this paper, all the specific features that these rooms have are taken into consideration and sound is evaluated by means of reproduction through high quality professional equipment. Also, a listening area is a small, exactly given place for optimal listening for sound control engineer.The optimal sound control room must provide a complete and clear perception of reproduced sound with all specific features, and the room\u27s spatial characteristics may not influence nor change the characteristics of the reproduced sound. Conjoint Analisys method is used to obtain estimation of the impact of the room objective acoustic quality parameters on the subjective assessment of the professional sound control room. Thereby, the use of modern statistical method (Conjoint Analysis - CA) shows dependence of one subjective parameter on more than one objective parameter. This principle determines more accurately real-life conditions, where all ratings are subject to complex dependence on more objective parameters

Komparativna mjerenja na hidrkustičkim pretvaračima

Mjerenja na hidroakustičkim pretvaračima u vodi su vrlo složena. Zahtijevaju posebnu mjernu opremu, kao i posebne mjerne prostore (npr. gluhi bazen). Uz to, i mehanička konstrukcija samih hidroakustičkih pretvarača mora biti u potpunosti završena kako bi se mogla provesti mjerenja u vodi. Zato je korisno prije završetka radova na hidroakustičkim pretvaračima provesti probna mjerenja u zraku, i na temelju tih mjerenja zaključiti, da li je konstrukcija mehaničkog pretvarača ispravna, i da li zadovoljava osnovne zahtjeve postavljene pri konstrukciji

Metoda evaluacije kvalitete akustike sobe temeljenoj na energetskim relacijama zvuka

Measuring procedure of achieving room acoustic quality parameters with impulse response is usually used as the basis for acoustical measuring PC based software. The objective parameters: clarity (C), definition (D) and ratio between reflected and direct energy (R) are defined with reflected, direct and total energy of sound. The relations are set in order to enable estimation of other parameters based on measurement of only one energy parameter. Based on measurements in two architectural identical, but according to acoustic characteristics two different rooms, and additional analysis and calculations connected with number of people in a hall, objective parameters are evaluated according to earlier adopted optimal conditions involving certain deviations from the values.Mjerni postupak postizanja parametara kvalitete zvuka prostorije impulsnim odzivom obično se koristi kao osnova za računalni software za akustično mjerenje. Jasnoća (C), definicija (D) i omjer između reflektirane i izravne energije (R) kao objektivni parametri definirani su reflektiranom, izravnom i ukupnom energijom zvuka. Odnosi su postavljeni tako da bi se omogućila procjena ostalih parametara na temelju mjerenja samo jednog parametra energije. Na temelju mjerenja u dvije arhitektonski identične, ali prema akustičnim svojstvima dvije različite prostorije te dodatnoj analizi i izračunima povezanima s brojem ljudi u dvorani, objektivni parametri se ocjenjuju prema ranije usvojenim optimalnim uvjetima koji uključuju određena odstupanja od vrijednosti

Sound source influence to the room acoustics quality measurement

Vrijednosti objektivnih parametara akustičke kvalitete prostora dobivaju se iz impulsnog odziva, koji se mjeri odgovarajućom opremom temeljenom na osobnom računalu, s dvije vrste zvučnika. Takvo mjerenje daje impulsni odziv koji je rezultat mjerenja cijelog sustava, koji se sastoji od prostora i primijenjene elektoakustičke opreme. Napravljeno je istraživanje koliki je stvarni utjecaj zvučnika na rezultate mjerenja. Impulsni odzivi mjereni su uvijek istom opremom, a mjerne točke su odabrane tako da budu na optimalnom mjestu za slušanje, i sva mjerenja su izvedena u istom prostoru. Zvučnici su smješteni na optimalnim i karakterističnim mjestima u prostoriji, i rotirani su oko vertikalne osi u cilju utvrđivanja utjecaja njihove pozicije i usmjerne karatkeristike na rezultate mjerenja objektivnih parametara akustičke kvalitete prostora.Objective parameters of the room acoustics quality are obtained from the impulse response, which is measured using the appropriate PC based acoustic measurement system with two types of loudspeakers. Such measurement gives the impulse response that is the result of measurement of the entire system, which consists of the room and electro acoustics equipment. In order to investigate the real influence of loudspeakers on the measurement results, the research was made in the same measuring conditions. Impulse responses were measured with the same measuring system. Measuring point was selected at the optimum listening position in the room, and all measurements were carried out in the same place. The loudspeakers were placed at the optimum and characteristic positions in the room, and rotated around their axes in order to determine the impact of their position and directivity characteristics on the measurement of objective parameters of room acoustic quality

Projektiranje akustičnih filtera metodom raspodjeljenih parametara

Prilikom projektiranja akustičkih filtara, velika je poteškoća proračun odgovarajuće frekvencijske karakteristike. Metoda raspodijeljenih parametara uz elektro-akustičke analogije omogućuje dobivanje realnih frekvencijskih karakteristika. Primjenom računala moguće je proračunati dimenzije i oblik akustičkog filtra odgovarajuće frekvencijske karakteristike i odgovarajuće razine gušenja

Optimizing acoustical quality of sound control room

Doktorski rad „Optimiranje akustičke kvalitete profesionalnoga prostora za slušanje“ rezultat je istraživanja akustičkih svojstava profesionalnih prostora za slušanje. Utvrđene su posebnosti tih prostora koje karakterizira vrlo velika važnost kvalitete zvuka u svrhu njegove obrade, pri čemu oni moraju biti akustički tako projektirani da vrijednosti svih njihovih parametara akustičke kvalitete imaju optimalne vrijednosti potrebne za postizanje najbolje moguće kvalitete slušanja. Izmjereni su realni profesionalni prostori za slušanje, i nakon toga je napravljena detaljna statistička analiza izmjerenih vrijednosti parametra, kao i rezultata subjektivnih ispitivanja, i to primjenom statističke metode analize glavnih komponenata i statističke metode združene analize parametara. Tim metodama utvrđeni su uvjeti mjerenja pod kojima se dobivaju najtočniji rezultati mjerenja, koji će u najvećoj mjeri korelirati sa subjektivnim ocjenama istih tih prostora. Matematičkom metodom združenih parametara određeni su koeficijenti utjecaja objektivnih parametara akustičke kvalitete na subjektivnu ocjenu. Nakon toga je napravljen matematički model funkcijske ovisnosti primjenom polinomne i racionalne funkcije koja prikazuje frekvencijsku ovisnost objektivnih parametara za uvjet postizanja optimalne kvalitete slušanja. U konačnici, izveden je i geometrijski model optimalnog prostora za slušanje, koji služi kao osnova za izradu računalnih simulacija u kojima su namjerno, na kontrolirani način mijenjani neki akustički uvjeti, i utvrđene su granice promjene tih određenih parametara akustičke kvalitete kod kojih dolazi do subjektivnih zamjećivanja promjene u kvaliteti slušanja.Ph. D. thesis entitled "Optimizing acoustical quality of sound control room" is the result of the study of acoustic properties of professional sound control rooms. The specificities of these rooms which are characterized by very high importance to have the high quality of sound for the purpose of its processing are determined. They must be acoustically designed so that the values of their acoustical quality parameters have optimal values necessary to achieve the best possible listening quality. The real sound control rooms were measured, and a detailed mathematical analysis of the measured parameter values was done, as well as the analysis of subjective tests results. This analysis was done applying the statistical method “Principal Components Analysis” (PCA) and statistical method “Conjoint Analysis” (CA). With those methods measuring conditions under which they receive the most accurate measurement results are defined, and which will have the best possible correlation with subjective evaluations of the same rooms. The mathematical model of functional dependency by using polynomial and rational functions was made. This model shows the frequency dependence of objective parameters provided to achieve the optimum listening quality. Finally, the geometric model of optimal sound control room is defined. Also, the values are defined, within which certain parameters has the just noticeable value change. In the introductory chapter an overview of types of professional sound control rooms, their basic characteristics and problems, and their basic design principles are given. In the second chapter an overview of measurement methods and measuring conditions defined for the purposes of research are given. Also, the objective room acoustic parameters which were considered are described, as well as the method of subjective acoustical quality test. The test conditions are defined and subjective acoustical quality parameters that were considered in the thesis are provided and described. In the third chapter an analysis of objective acoustical quality parameters for professional sound control rooms is given. Structural parameters (dimensions and volume) of professional sound control rooms are shown, as well as the results of statistical analisys of the objective acoustical quality parameters. A statistical analisys with the method of principal components analysis (PCA) of measurement results in different conditions was made. In the fourth chapter the subjective parameters of acoustical quality of professional sound control rooms were analyzed. An algorithm for evaluating the acoustical quality of the room with respect to each subjective parameter of acoustical quality of the room is presented. The impact of a certain objective parameters of acoustic qualities of the room on the parameters of a subjective evaluation of acoustic quality is assessed. In the fifth chapter mathematical model of optimal sound control room is designed. The functional frequency dependence of objective parameters of acoustic quality of the room is determined, where the condition is to achieve the best subjective assessments. The functional dependence is determined by polynomial and rational functions. The geometric model used in computer simulation is also designed. In the sixth chapter a computer simulation of sound control room is presented. In the simulation some parameters of acoustical quality are changed, and the values where the change is just noticeable are determined. In the seventh chapter, "Conclusion", all the results of research done in this Ph. D. thesis are summarized. In this way, the whole objective measurements and subjective assessments of acoustical quality of professional sound control room are completely covered. The mathematic and geometric models for computer simulation are made. Those models and simulations of acoustic properties provide a full image of the problem, and allow us to propose the solutions for the problems of acoustical design of professional sound control rooms. The complex dependencies of the results of the objective measurements and subjective assessments of acoustic quality is shown, as well as the complexity of the optimization process of acoustic parameters in order to achieve the acoustically optimal sound control room

Optimizing acoustical quality of sound control room

Doktorski rad „Optimiranje akustičke kvalitete profesionalnoga prostora za slušanje“ rezultat je istraživanja akustičkih svojstava profesionalnih prostora za slušanje. Utvrđene su posebnosti tih prostora koje karakterizira vrlo velika važnost kvalitete zvuka u svrhu njegove obrade, pri čemu oni moraju biti akustički tako projektirani da vrijednosti svih njihovih parametara akustičke kvalitete imaju optimalne vrijednosti potrebne za postizanje najbolje moguće kvalitete slušanja. Izmjereni su realni profesionalni prostori za slušanje, i nakon toga je napravljena detaljna statistička analiza izmjerenih vrijednosti parametra, kao i rezultata subjektivnih ispitivanja, i to primjenom statističke metode analize glavnih komponenata i statističke metode združene analize parametara. Tim metodama utvrđeni su uvjeti mjerenja pod kojima se dobivaju najtočniji rezultati mjerenja, koji će u najvećoj mjeri korelirati sa subjektivnim ocjenama istih tih prostora. Matematičkom metodom združenih parametara određeni su koeficijenti utjecaja objektivnih parametara akustičke kvalitete na subjektivnu ocjenu. Nakon toga je napravljen matematički model funkcijske ovisnosti primjenom polinomne i racionalne funkcije koja prikazuje frekvencijsku ovisnost objektivnih parametara za uvjet postizanja optimalne kvalitete slušanja. U konačnici, izveden je i geometrijski model optimalnog prostora za slušanje, koji služi kao osnova za izradu računalnih simulacija u kojima su namjerno, na kontrolirani način mijenjani neki akustički uvjeti, i utvrđene su granice promjene tih određenih parametara akustičke kvalitete kod kojih dolazi do subjektivnih zamjećivanja promjene u kvaliteti slušanja.Ph. D. thesis entitled "Optimizing acoustical quality of sound control room" is the result of the study of acoustic properties of professional sound control rooms. The specificities of these rooms which are characterized by very high importance to have the high quality of sound for the purpose of its processing are determined. They must be acoustically designed so that the values of their acoustical quality parameters have optimal values necessary to achieve the best possible listening quality. The real sound control rooms were measured, and a detailed mathematical analysis of the measured parameter values was done, as well as the analysis of subjective tests results. This analysis was done applying the statistical method “Principal Components Analysis” (PCA) and statistical method “Conjoint Analysis” (CA). With those methods measuring conditions under which they receive the most accurate measurement results are defined, and which will have the best possible correlation with subjective evaluations of the same rooms. The mathematical model of functional dependency by using polynomial and rational functions was made. This model shows the frequency dependence of objective parameters provided to achieve the optimum listening quality. Finally, the geometric model of optimal sound control room is defined. Also, the values are defined, within which certain parameters has the just noticeable value change. In the introductory chapter an overview of types of professional sound control rooms, their basic characteristics and problems, and their basic design principles are given. In the second chapter an overview of measurement methods and measuring conditions defined for the purposes of research are given. Also, the objective room acoustic parameters which were considered are described, as well as the method of subjective acoustical quality test. The test conditions are defined and subjective acoustical quality parameters that were considered in the thesis are provided and described. In the third chapter an analysis of objective acoustical quality parameters for professional sound control rooms is given. Structural parameters (dimensions and volume) of professional sound control rooms are shown, as well as the results of statistical analisys of the objective acoustical quality parameters. A statistical analisys with the method of principal components analysis (PCA) of measurement results in different conditions was made. In the fourth chapter the subjective parameters of acoustical quality of professional sound control rooms were analyzed. An algorithm for evaluating the acoustical quality of the room with respect to each subjective parameter of acoustical quality of the room is presented. The impact of a certain objective parameters of acoustic qualities of the room on the parameters of a subjective evaluation of acoustic quality is assessed. In the fifth chapter mathematical model of optimal sound control room is designed. The functional frequency dependence of objective parameters of acoustic quality of the room is determined, where the condition is to achieve the best subjective assessments. The functional dependence is determined by polynomial and rational functions. The geometric model used in computer simulation is also designed. In the sixth chapter a computer simulation of sound control room is presented. In the simulation some parameters of acoustical quality are changed, and the values where the change is just noticeable are determined. In the seventh chapter, "Conclusion", all the results of research done in this Ph. D. thesis are summarized. In this way, the whole objective measurements and subjective assessments of acoustical quality of professional sound control room are completely covered. The mathematic and geometric models for computer simulation are made. Those models and simulations of acoustic properties provide a full image of the problem, and allow us to propose the solutions for the problems of acoustical design of professional sound control rooms. The complex dependencies of the results of the objective measurements and subjective assessments of acoustic quality is shown, as well as the complexity of the optimization process of acoustic parameters in order to achieve the acoustically optimal sound control room

Optimizing acoustical quality of sound control room

Doktorski rad „Optimiranje akustičke kvalitete profesionalnoga prostora za slušanje“ rezultat je istraživanja akustičkih svojstava profesionalnih prostora za slušanje. Utvrđene su posebnosti tih prostora koje karakterizira vrlo velika važnost kvalitete zvuka u svrhu njegove obrade, pri čemu oni moraju biti akustički tako projektirani da vrijednosti svih njihovih parametara akustičke kvalitete imaju optimalne vrijednosti potrebne za postizanje najbolje moguće kvalitete slušanja. Izmjereni su realni profesionalni prostori za slušanje, i nakon toga je napravljena detaljna statistička analiza izmjerenih vrijednosti parametra, kao i rezultata subjektivnih ispitivanja, i to primjenom statističke metode analize glavnih komponenata i statističke metode združene analize parametara. Tim metodama utvrđeni su uvjeti mjerenja pod kojima se dobivaju najtočniji rezultati mjerenja, koji će u najvećoj mjeri korelirati sa subjektivnim ocjenama istih tih prostora. Matematičkom metodom združenih parametara određeni su koeficijenti utjecaja objektivnih parametara akustičke kvalitete na subjektivnu ocjenu. Nakon toga je napravljen matematički model funkcijske ovisnosti primjenom polinomne i racionalne funkcije koja prikazuje frekvencijsku ovisnost objektivnih parametara za uvjet postizanja optimalne kvalitete slušanja. U konačnici, izveden je i geometrijski model optimalnog prostora za slušanje, koji služi kao osnova za izradu računalnih simulacija u kojima su namjerno, na kontrolirani način mijenjani neki akustički uvjeti, i utvrđene su granice promjene tih određenih parametara akustičke kvalitete kod kojih dolazi do subjektivnih zamjećivanja promjene u kvaliteti slušanja.Ph. D. thesis entitled "Optimizing acoustical quality of sound control room" is the result of the study of acoustic properties of professional sound control rooms. The specificities of these rooms which are characterized by very high importance to have the high quality of sound for the purpose of its processing are determined. They must be acoustically designed so that the values of their acoustical quality parameters have optimal values necessary to achieve the best possible listening quality. The real sound control rooms were measured, and a detailed mathematical analysis of the measured parameter values was done, as well as the analysis of subjective tests results. This analysis was done applying the statistical method “Principal Components Analysis” (PCA) and statistical method “Conjoint Analysis” (CA). With those methods measuring conditions under which they receive the most accurate measurement results are defined, and which will have the best possible correlation with subjective evaluations of the same rooms. The mathematical model of functional dependency by using polynomial and rational functions was made. This model shows the frequency dependence of objective parameters provided to achieve the optimum listening quality. Finally, the geometric model of optimal sound control room is defined. Also, the values are defined, within which certain parameters has the just noticeable value change. In the introductory chapter an overview of types of professional sound control rooms, their basic characteristics and problems, and their basic design principles are given. In the second chapter an overview of measurement methods and measuring conditions defined for the purposes of research are given. Also, the objective room acoustic parameters which were considered are described, as well as the method of subjective acoustical quality test. The test conditions are defined and subjective acoustical quality parameters that were considered in the thesis are provided and described. In the third chapter an analysis of objective acoustical quality parameters for professional sound control rooms is given. Structural parameters (dimensions and volume) of professional sound control rooms are shown, as well as the results of statistical analisys of the objective acoustical quality parameters. A statistical analisys with the method of principal components analysis (PCA) of measurement results in different conditions was made. In the fourth chapter the subjective parameters of acoustical quality of professional sound control rooms were analyzed. An algorithm for evaluating the acoustical quality of the room with respect to each subjective parameter of acoustical quality of the room is presented. The impact of a certain objective parameters of acoustic qualities of the room on the parameters of a subjective evaluation of acoustic quality is assessed. In the fifth chapter mathematical model of optimal sound control room is designed. The functional frequency dependence of objective parameters of acoustic quality of the room is determined, where the condition is to achieve the best subjective assessments. The functional dependence is determined by polynomial and rational functions. The geometric model used in computer simulation is also designed. In the sixth chapter a computer simulation of sound control room is presented. In the simulation some parameters of acoustical quality are changed, and the values where the change is just noticeable are determined. In the seventh chapter, "Conclusion", all the results of research done in this Ph. D. thesis are summarized. In this way, the whole objective measurements and subjective assessments of acoustical quality of professional sound control room are completely covered. The mathematic and geometric models for computer simulation are made. Those models and simulations of acoustic properties provide a full image of the problem, and allow us to propose the solutions for the problems of acoustical design of professional sound control rooms. The complex dependencies of the results of the objective measurements and subjective assessments of acoustic quality is shown, as well as the complexity of the optimization process of acoustic parameters in order to achieve the acoustically optimal sound control room