Wyniki wyszukiwania - BazTech

1

The influence of diffuser configuration in a reverberation room on sound absorption coefficient measurements

Mleczko Dominik

Materiały Budowlane

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2025

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nr 8

213--219

EN

The aim of the study was to evaluate the impact of diffuser arrangement in a reverberation room on the values of the sound absorption coefficient determined from reverberation time measurements in accordance with ISO 354. Measurements were carried out for four configurations, both with and without a sound‑absorbing sample. The results showed that the diffuser layout can affect the outcomes, particularly at low frequencies, confirming the sensitivity of the measurements to acoustic field conditions.

PL

W artykule zaprezentowano ocenę wpływu rozmieszczenia rozpraszaczy w komorze pogłosowej na wartość współczynnika pochłaniania dźwięku wyznaczanego na podstawie czasu pogłosu zgodnie z ISO 354. Badania wykonano w czterech konfiguracjach, z materiałem pochłaniającym i bez. Wykazano, że układ rozpraszaczy może wpływać na uzyskiwane wyniki, szczególnie w zakresie niskich częstotliwości, co potwierdza wrażliwość pomiarów na warunki pola akustycznego.

2

Model analysis of the church in Oborki taking into account its geometric and material parameters

Marchacz Michał, Żaba Antonina

Materiały Budowlane

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2025

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nr 10

113--118

EN

The paper presents the influence of the historical research carried out on the object on the possible directions for giving its a new function. Simulation studies of the acoustic parameters of the interior have made it possible to determine the impact of restoring the original emporium on the acoustic parameters of the building – the speech intelligibility index STI and clarity index C80. The influence of filling the interior with listeners within the currently existing structure as well as the one modified by the formerly existing music choir was indicated. The study confirmed the good acoustic quality of the interior of St. Apostels Peter and Paul's Church in Oborki.

PL

W artykule zaprezentowano wpływ prowadzonych badań historycznych obiektu na możliwe kierunki nadania mu nowej funkcji użytkowej. Przeprowadzone badania symulacyjne dotyczące parametrów akustycznych wnętrza pozwoliły określić wpływ przywrócenia pierwotnie występującej we wnętrzu empory na parametry akustyczne obiektu – wskaźniki zrozumiałości mowy STI i klarowności C80. Wskazano wpływ wypełnienia słuchaczami w obrębie obecnie istniejącej zabudowy wnętrza, jak i zmodyfikowanej o istniejący dawniej chór muzyczny. Prowadzone badania potwierdziły dobrą jakość akustyczną wnętrza kościoła Świętych Apostołów Piotra i Pawła w Obórkach.

3

Acoustics of the interior of the church in the context of its geometric and material parameters

Marchacz Michał, Żaba Antonina

Materiały Budowlane

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2025

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nr 8

188--193

EN

Historic religious buildings often lose their original function of use. The search for new ways of exploiting such buildings can ensure that they remain in good condition in the future. The authors present acoustic tests of the existing state of the interior of the church of St. Apostles Peter and Paul in Obórki. The authors determined selected parameters for the acoustic assessment of the interior in the context of the possibility of adapting the interior to a different mode of use.

PL

Zabytkowe obiekty sakralne często tracą swoją pierwotną funkcję użytkową. Poszukiwanie nowych sposobów eksploatacji takich obiektów może zapewnić ich utrzymanie w dobrym stanie w przyszłości. W artykule zaprezentowano wyniki badań akustycznych stanu istniejącego wnętrza kościoła pw. Świętych Apostołów Piotra i Pawła w Obórkach. Określono wybrane parametry oceny akustycznej wnętrza w kontekście możliwości adaptacji wnętrza do innego sposobu użytkowania.

4

Experimental and Numerical Investigations of Acoustic Variations in a Classroom Environment

Chauhan Amit Kumar Singh, Vedrtnam Ajitanshu, Pawar Suryappa Jayappa

Archives of Acoustics

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2025

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Vol. 50, nr 1

147--157

EN

The acoustic behaviour of a classroom is vital for an effective teaching-learning process. The present work aims to experimentally determine the acoustic performance of a typical classroom. The full-scale experiment was conducted at the Seminar Hall, the Department of Applied Mechanics, MNNIT Allahabad, Prayagraj, using a method with limited resource requirements. The Seminar Hall was divided into four planes by threads, and the sound pressure level (SPL) was measured at 30 coordinates in each plane for the specified sound source location. Data were collected from three different sound source locations. The study revealed that the sound source location and frequency significantly influence the sound pressure levels in the classroom, impacting its acoustic performance. The broader implications of interior materials, such as wall material and the position of elements like the teaching board, door, and podium, are highlighted as critical considerations for future classroom acoustic optimization. Furthermore, a numerical model was developed to predict the variation in the SPL with change in the sound source locations and frequencies. The collected data validated with the finite element (FE) model. The verification experiments for the modeling results were performed for each plane. The results of the FE model and experiments were found consistent across all four planes of the seminar hall and the various sound source locations.

5

Theoretical and numerical studies of low-frequency reverberant sound field in coupled rooms

Meissner Mirosław

Vibrations in Physical Systems

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2024

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Vol. 35, nr 3

art. no. 2024314

EN

The paper examines the low-frequency reverberation sound field in coupled-room systems. In theoretical model, the modal expansion of sound pressure was applied, while in numerical procedure, the discrete Hilbert transform was used to determine the amplitude of decaying sound. Computer simulations were performed for a room system consisting of two connected rectangular rooms. Eigenfunctions and eigenfrequencies of this system were determined by the finite element method. Simulation results showed that for the hard-walled room system the sound decay is almost exponential for frequencies of modes localized in one of the subrooms. Acoustical treatment of the ceiling significantly reduced reverberation. However, due to beating effects and modal overlap, a large irregularity of sound decay curves has occurred. This makes it difficult to correctly qualify the sound decay, because in this case it is practically impossible to characterize the reverberation process with only one or at most two decay times.

6

Combined Evaluation of Room Acoustic Descriptors in Different Structural Configurations via ODEON Simulations and Artificial Neural Networks

Do Nascimento Eriberto Oliveira, Zannin Paulo Henrique Trombetta

Archives of Acoustics

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2024

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Vol. 49, nr 4

543--556

EN

This study evaluated the combined sensitivity analysis of several room acoustic descriptors: reverberation time (T30), center time (Ts), early decay time (EDT), definition (D50), clarity (C50), useful-to-detrimental sound ratio (U50), and speech transmission index (STI); and also it assessed how these descriptors responded jointly to different acoustic-structural factors. The first-order factors were background noise (A), acoustic ceiling tile sound absorption coefficient (B), confinement (C), and occupancy (D), along with their interaction effects. A novel method is proposed for this joint evaluation of sensitivity factors. This method involves in situ measurements and an unreplicated 2^4 factorial design, which has been validated by ODEON software. The significance of input factors is determined using artificial neural networks (ANN) and the modified profile method (MPM), validated by multiple linear regression (MLR). Three significant correlation groups are identified at p < 0:05: group 1 (EDT, T30, Ts), group 2 (C50, D50), and group 3 (U50, STI). The ceiling material sound absorption (B) is found to affect reverberation (groups 1 and 2), while background noise (A) impacts STI and U50. A weak correlation is found between D50 and STI. These results are confirmed by the MLR and MPM methods.

7

Miniature omnidirectional sound sources used in acoustic scale modeling - measurements and validation

Chojnacki Bartłomiej

Vibrations in Physical Systems

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2022

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Vol. 33, nr 2

art. no. 2022201

EN

Acoustic measurements such as scale modeling measurements require a particular type of miniature omnidirectional sound source. The most important aspects of those devices are small sizes (usually below 100 mm in diameter) and different frequency ranges compared to traditional, omnidirectional sound sources used in room acoustics. The required frequency range differs regarding the used scale factor in different models, which leads to the troubles in frequent source changes and the need for a unique source design for every model. The project will present the recent achievement in miniature omnidirectional sound sources development. The optimal sound sources for the given measurement functions were developed based on the previous numerical simulations and experiments such as FEM sound directivity simulations or transducers' parameters tolerance testing. The sound sources presented are used for applications such as acoustic sound insulation scale measurements (frequency range 800 ÷ 63 000 Hz), scaled reverberation chamber measurements (300 ÷ 80 000 Hz), or acoustic reduction models measurements (400 ÷ 70 000 Hz). The paper will cover a detailed technical explanation of the laboratory environment's source construction aspects and validation measurements.

8

Application of an ambisonic microphone for the measurements of room acoustic parameters

Jasiński Maciej, Żera Jan

Vibrations in Physical Systems

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2022

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Vol. 33, nr 3

art. no. 2022312

EN

The most commonly used measurement technique in room acoustics employs a single omnidirectional microphone for recording the room impulse response and further derivation of such acoustical parameters as T30, EDT, C50 or C80. Instead, ambisonic technology makes it possible to measure a spatial room impulse response. Ambisonics decomposes the signal from the spherical microphone array into spherical harmonics to shape the directivity. Ambisonics lets to go beyond basic acoustical parameters and allows to determine spatial features of a sound field at the measurement point. This study presents the comparison of fundamental acoustic parameters measured in the recording studio by an actual omnidirectional microphone and virtual omnidirectional microphones derieved from ambisonic microphones of the first and third order. The results show the usefulness of ambisonic technology in terms of assessing basic room parameters.

9

Mineralna izolacja natryskowa jako materiał poprawiający akustykę wnętrz

Marchacz Michał, Nowoświat Artur

Materiały Budowlane

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2022

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nr 8

14--16

PL

W artykule przedstawiono parametry akustyczne pianki natryskowej. Wyniki badań współczynnika pochłaniania dźwięku w komorze pogłosowej wskazują, że ma ona dobre właściwości dźwiękochłonne. Wyniki zweryfikowano przez zastosowanie materiału w pomieszczeniu o przeznaczeniu sakralnym w kształcie kopuły i o kubaturze 14 850 m3. Po zastosowaniu materiału czas pogłosu uległ znacznemu obniżeniu, co poprawiło warunki pogłosowe w pomieszczeniu.

EN

The article presents the acoustic parameters of the foam spray. The results of sound absorption coefficient obtained in the reverberation chamber show that the material has good soundproofing properties. Results were verified by applying the material in a dome-shaped sacral room with a cubature of 14 850 m3. Thanks to the use of the material, the reverberation time was significantly reduced. It has improved the reverberation conditions in the room.

10

Wibroizolacja to kosztowna fanaberia czy praktyczne rozwiązanie inżynierskie?

Tekielak Mateusz

Chłodnictwo i Klimatyzacja

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2022

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nr 1

38--39

PL

Większość krajów europejskich wdraża lokalnie przepisy prawne dotyczące wymagań akustycznych we wszystkich rodzajach budynków: publicznych, jednorodzinnych, przemysłowych. Nowo budowane obiekty muszą być zgodne z określonymi normami i przepisami budowlanymi, natomiast żadne przepisy nie zawierają wytycznych dotyczących renowacji starych budynków w zakresie akustyki. Tymczasem kwestie komfortu akustycznego stały się ważne dla wszystkich użytkowników, bez względu na datę powstania obiektu. Warto to brać pod uwagę i zadbać o komfort akustyczny na możliwie najwcześniejszym etapie prac w budynku - będzie prościej i taniej.

11

Ocena jakości akustycznej pomieszczeń biurowych typu open space z uwzględnieniem normy ISO 22955:2021

Mikulski Witold

Bezpieczeństwo Pracy : nauka i praktyka

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2022

|

nr 12

22-27

PL

W PN-B-2151-4:2015 wyróżnia się dwa typy wielkopowierzchniowych pomieszczeń pracy: grupę 1 - pomieszczenia biurowe open space (inaczej zwane otwartymi pomieszczeniami do prac administracyjnych), sale operacyjne banków i urzędów, biura obsługi klienta, oraz grupę 2 - centra obsługi telefonicznej. W każdej z tych grup określona jest minimalna chłonność akustyczna pomieszczenia. W PN-EN ISO 3382-3:2012 wprowadzono cztery inne kryteria akustyczne pomieszczeń, dotyczące grupy 2. Do stanowisk pracy lub wymienionych pomieszczeń odnoszą się także kryteria związane z dopuszczalnym hałasem, określone w PN-N-01307:1994 oraz PN-B-02151-2:2018. Omawiane kryteria opracowano od 28 do czterech lat wstecz i w wielu przypadkach nie są one w pełni dostosowane do obecnie eksploatowanych pomieszczeń. Skutkiem tego było wprowadzenie w nowej normie ISO 22955:2021 nowego podziału wielkopowierzchniowych pomieszczeń pracy na sześć klas, w tym klasy pomieszczeń przeznaczonych do pracy biurowej, ale bez wyposażenia. W artykule omówiono wymagania oraz podano kryteria oceny pomieszczeń biurowych open space według ISO 22955:2021 oraz norm: PN-N-01307, PN-B-02151-2, PN-B-02151-4 i PN-EN ISO 3382-3.

EN

The Polish standard PN-B-02151-4: 2015 distinguishes two types of large-area work rooms: 1 - open plan offices, operating rooms for banks and offices, customer service offices and 2 - call centres. In each of these types, criteria for the minimum sound absorption of the room are defined. The PN-EN ISO 3382-32012 specifies four other acoustic criteria for rooms, but referring only to rooms type 2. For workplaces or the above-mentioned the rooms are also subject to the criteria for permissible noise specified in the PN-N-01307:1994 and the PN-B-02151-2:2018 standards. Above the criteria were developed from 28 to 4 years ago and in many cases are not fully adapted to the currently used rooms. As a result, the new ISO 22955: 2021 introduced a new division of open plan offices spaces/rooms. There are five types of used rooms and an additional class i.e. a room intended for office work, but without equipment. The article will discuss the acoustic requirements and the evaluation criteria of the rooms according to ISO 22955:2021 and the standards: PN-N-01307, PN-B-02151-2, PN-B-02151-4 and PN-EN ISO 3382-3.

12

Impact of Wall Impedance Phase Angle on Indoor Sound Field and Reverberation Parameters Derived from Room Impulse Response

Meissner Mirosław, Zieliński Tomasz

Archives of Acoustics

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2022

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Vol. 47, No. 3

343--353

EN

Accurate definition of boundary conditions is of crucial importance for room acoustic predictions because the wall impedance phase angle can affect the sound field in rooms and acoustic parameters applied to assess a room reverberation. In this paper, the issue was investigated theoretically using the convolution integral and a modal representation of the room impulse response for complex-valued boundary conditions. Theoretical considerations have been accompanied with numerical simulations carried out for a rectangular room. The case of zero phase angle, which is often assumed in room acoustic simulations, was taken as a reference, and differences in the sound pressure level and decay times were determined in relation to this case. Calculation results have shown that a slight deviation of the phase angle with respect to the phase equal to zero can cause a perceptual difference in the sound pressure level. This effect was found to be due to a change in modal frequencies as a result of an increase or decrease in the phase angle. Simulations have demonstrated that surface distributions of decay times are highly irregular, while a much greater range of the early decay time compared to the reverberation time range indicates that a decay curve is nonlinear. It was also found that a difference between the decay times predicted for the complex impedance and real impedance is especially clearly audible for the largest impedance phase angles because it corresponds approximately to 4 just noticeable differences for the reverberation metrics.

13

Acoustic Characterization of a Room : Study Case Between Simulation and a Portable Method

Ibarra-Zarate David, Padilla-Ortiz Ana Laura

Archives of Acoustics

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2020

|

Vol. 45, No. 1

153--163

EN

Large venues and auditoriums are commonly associated with their astounding architecture. Their acoustic quality is an essential factor in its qualification as a great and functional, or a badly designed place. However, acoustics is often overlooked during the design stage of a building due to the complexity and high cost of the measurements involved. For this reason, it is important to explore more accessible ways to implement acoustics evaluations. The aim of this work is to compare typical experimental measuring methods and the use of mobile devices to assess the acoustic quality of a room. These measurements are contrasted with the software simulation of the same acoustical space. The results show that the mobile system can be used for professional measurements with low restrictions in the frequency range of interest of this study (90 Hz to 4000 Hz).

14

Prediction of low-frequency sound field in rooms with complex-valued boundary conditions on walls

Meissner Mirosław

Vibrations in Physical Systems

|

2019

|

Vol. 30, nr 1

art. no. 2019127

EN

A modal representation of a room impulse response has been used to formulate expressions for low-frequency sound field in rooms of arbitrary shape. Based on theoretical results, a simulation program has been developed to predict a sound pressure distribution and a room transfer function for rectangular enclosure having walls covered by a material of complex impedance. Calculation results have shown that changes in the wall reactance entail a substantial modification of a sound pressure distribution. Furthermore, an influence of wall reactance on the room transfer function was investigated and it was discovered that a change in a reactance sign causes a shift in frequencies of modal vibrations excited in the room.

15

Effectiveness of acoustic banners depending on their arrangement in the concert hall - case study

Kozłowski Piotr Z.

Vibrations in Physical Systems

|

2019

|

Vol. 30, nr 1

art. no. 2019141

EN

One of the most frequently used methods of adjusting the room acoustics of concert halls is the temporary introduction of additional acoustic absorption in the form of acoustic banners. Banners are implemented in the form of fabric surfaces placed vertically or horizontally along the walls of concert halls. In practice, one or two layers of heavyweight fabrics are used, characterized by a high value of the sound absorption coefficient. Simplified methods of designing acoustic banners assume estimating the effectiveness of adjusting the reverberation time on the basis of the static theory. The paper presents the results of measuring the effectiveness of acoustic banners carried out in the concert hall. The possibility of tuning the interior acoustics was verified depending on the position of the banner in the room as well as the degree of its opening.

16

Projektowanie adaptacji akustycznej otwartych pomieszczeń do prac administracyjnych. Część 1. Projektowanie podstawowe

Mikulski Witold

Materiały Budowlane

|

2019

|

nr 8

16--20

PL

Projektowanie akustyczne pomieszczeń biurowych open space polega na takim uwzględnieniu w pomieszczeniu różnych wyrobów dźwiękochłonnych, aby uzyskać wymagane przepisami warunki akustyczne. W artykule projektowanie podzielono na dwa etapy. Etap pierwszy, wymagany przez przepisy polskie, to uzyskanie w pomieszczeniu wymaganej chłonności akustycznej. Natomiast etap drugi polega na takiej aranżacji akustycznej pomieszczenia i stanowisk pracy, aby uzyskać w nim wymagane warunki propagacji (a właściwie separacji) dźwięków mowy między stanowiskami pracy. Zewzględu na objętość, artykuł podzielono na dwie części. W części pierwszej opisano pierwszy etap projektowania (podano metodę obliczeniową wg PN-B-02151-4:2015 i przykład). W części drugiej, w następnym artykule, opisany zostanie etap drugi projektowania wraz z podaniem przykładu (z wykorzystaniem programu ODEON).

EN

The acoustic design of the open plan office consists in taking into account various sound-absorbing products in the room to achieve the required acoustic conditions. In the article design is divided into two stages. The first stage, obligatory by Polish regulations, is to obtain the room's required sound absorption. The second stage consists in such an acoustic arrangement of the room and workstations to obtain the required conditions for the propagation (or actually separation) of speech sounds between workstations. Due to the volume, the article has been divided into two parts. The first part (this one) describes the first design stage (the calculation method according to PN-B-02151-4:2015 standard and example are given). In the second part, in the next article, the second design stage (using the ODEON software) will be described.

17

Projektowanie adaptacji akustycznej otwartych pomieszczeń do prac administracyjnych. Część 2. Projektowanie dodatkowe

Mikulski Witold

Materiały Budowlane

|

2019

|

nr 9

82--85

PL

Projektowanie akustyczne otwartych pomieszczeń do prac administracyjnych (tzw. biurowych open space) można podzielić na dwa etapy. Etap pierwszy, obligatoryjny (podstawowy) wymagany przez przepisy, zakłada uzyskanie w pomieszczeniu wymaganych warunków pogłosowych (odpowiednio dużej chłonności akustycznej; omówiony został w artykule autora w „Materiałach Budowlanych” nr 8/2019). Etap drugi (dodatkowy) polega na takiej aranżacji pomieszczeń i stanowisk pracy oraz uwzględnieniu w pomieszczeniu różnych dodatkowych wyrobów dźwiękochłonnych, np. ekranów akustycznych, aby uzyskać w nim wymagane warunki propagacji (a właściwie separacji) dźwięków mowy między stanowiskami pracy. W ramach projektowania dodatkowego podano wyniki obliczeń metodą wg PN-EN ISO 3382-3:2012 siedmiu wariantów adaptacji akustycznej pomieszczenia.

EN

Acoustic design of open plan office can be divided into two stages. The first stage, obligatory by Polish regulations, is to obtain the room's required sound absorption. It was discussed in the author's article in "Building Materials" No. 8/2019. The second (additional) stage consists in such arrangement of rooms and work stations and taking into account various additional sound-absorbing products, e.g. acoustic screens, in order to obtain the required conditions for the propagation (or actually separation) of speech sounds between workplaces. As part of the additional design, results of calculations according to the EN ISO 3382-3:2012 method of seven variants of the room's acoustic treatment are given.

18

Adaptation of coutyards into covered and glazed atriums and its impact on the level of acoustic comfort inside – case study

Ziarko B.

Technical Transactions

|

2018

|

Vol. 115, iss. 9

133--140

EN

Increasingly popular, in the area of modernization or revitalization of historic buildings, is the creation of a roof that is often fully glazed over the inner courtyard, thus creating a new spacious interior capable of performing many functions. The acoustics evaluation undertaken in this article was carried out on the basis of measurements and simulation of reverberation time in The Home Army Museum building in Cracow.

PL

Coraz popularniejsze staje się w ramach rewitalizacji zabytkowych obiektów wykonanie zadaszenia nad dziedzińcem wewnętrznym i stworzenia tym samym nowego przestronnego wnętrza mogącego pełnić bogate funkcje. Podjęta w artykule ocena akustyki wnętrza została wykonana na podstawie pomiarów i symulacji czasu pogłosu w budynku Muzeum Armii Krajowej w Krakowie.

19

Wpływ kubatury sal do indywidualnych prób muzycznych na akustykę w ich wnętrzu

Warzocha K.

Materiały Budowlane

|

2018

|

nr 8

20--22

PL

W artykule omówiono najczęściej popełniane błędy przy projektowaniu sal do prób muzycznych. Szczególną uwagę zwrócono na zbyt małą kubaturę pomieszczeń, w których instrumenty muzyczne generują dźwięki o parametrach przewyższających dopuszczalne wartości. Na podstawie przeprowadzonych analiz przedstawiono wpływ kubatury sal do indywidualnych prób muzycznych na poziom ciśnienia akustycznego w ich wnętrzu. Zaproponowano podział sal, ze względu na rodzaj instrumentu muzycznego, jako jeden ze sposobów poprawy procesu projektowania tego typu pomieszczeń.

EN

The article discusses the most common mistakes made during the design of rehearsal music rooms. Particular attention has been paid to the insufficient rooms' volume, where musical instruments generate sounds with parameters exceeding the permissible values. Based on the analyzes carried out, the influence of volume of individual rehearsal music rooms on the sound pressure level in their interior was presented. A division of rooms was proposed, due to the type of musical instrument, as one of the ways to improve the design process of this type of rooms.

20

Speech Intelligibility Test for Polish Language – Relation to the Acoustic Properties of Classrooms and Comparison to Other Languages

Radosz J.

Archives of Acoustics

|

2018

|

Vol. 43, No. 1

129--135

EN

Numerous studies have shown that teachers often speak louder in classrooms because of the acoustic properties of the spaces. To improve the acoustics in classrooms, it is necessary to develop relevant acoustic criteria. Existing evaluation scales for parameters of room acoustics have been developed on the basis of studies of adults for a variety of languages (e.g. Dutch and English). One of the issues still not fully recognized is the effect of the respondents’ language and age on the results of speech intelligibility tests. The aim of the study was to recognize the possibility of applying some international guidelines for room acoustics developed on the basis of adult studies to classrooms in Polish schools. This paper presents a study of the speech intelligibility of Polish-speaking children (10–13 years old) in conjunction with parameters of room acoustics. It also compares studies of speech intelligibility for other languages. The study confirmed a relationship between the results of speech intelligibility tests and speech transmission index STI for classrooms with varied acoustics. It also showed that the results of Polish word test are similar to results of English tests (Anderson, Kalb, 1987; Jacob et al., 1990).