This theoretical diploma thesis deals with room acoustics and the closely related issue of reverberation. Part of the work is a drafting of acoustic modifications of the church based on manual calculation, which was further modified in a specialized software Odeon Room Acoustics Program. For the surrounding buildings of the church was created a study of the noise in a program Hluk+ in order to assess what will be the noise impact of this new building on its surroundings. On the basis of specialization was created several proposals for the design of the church. The approximate proposal of the double-plated dome, a system of drainage of the coupling neck, and the ways the anchor of the hard large-format window glazing. The result of the work is suitable design of acoustic adjustments and improvement of the listening qualities for the future construction of this church.

En äldre industribyggnad är oftast byggd i hårda material så som tegel, stål och plåt vilket alla ger upphov till hög andel reflektioner av ljudenergi. Absorptionsnivån i dessa material är låga vilket leder till långa efterklangstider. Att montera in akustikreglerande åtgärder i dessa byggnader står i konflikt med att äldre industribyggnader ofta har ett kulturhistoriskt värde.  Syftet med arbetet var att undersöka möjligheten till att genomföra akustikreglering i en kulturhistoriskt värdefull byggnad utan att väsentligt påverka detta värde. Avseende ambitionsnivån ur akustisk synpunkt var målet att halvera efterklangstiden.  De genomförda efterklangstidsmätningarna visar på en relativ lång efterklangstid i mellanregistret och en kortare vid låga och höga frekvenser. Resultatet av de beräkningar som är genomförda visar att i den mindre, av två stycken, hyttan kan målet med en halverad efterklangstid uppnås för majoriteten av oktavbanden. Åtgärdsförslaget för den större hyttan skulle däremot inte leda till att målet uppfylls fullt ut, utan för detta skulle ytterligare åtgärder behöva sättas in. Hänsyn till hyttans kulturvärde motiverar dock att en längre efterklangstid kan accepteras. / An older industrial building is usually built in hard materials such as brick, steel and sheet metal, all of which give rise to a high proportion of reflections of sound energy. The absorption level in these materials is low, which leads to long reverberation times. Installing acoustic regulatory measures in these buildings conflicts with the fact that older industrial buildings often have a cultural-historical value.  The purpose of this work was to investigate the possibility of implementing acoustic regulations in a culturally and historically valuable building without substantially affecting its cultural value. Regarding the level of ambition from an acoustic perspective, the objective was to halve the reverberation time.  The measured reverberation time shows a relative long reverberation time in the mid frequencies and a shorter one at low and high frequencies. The results of the calculations that have been carried out show that in the smaller production hall, of two, the objective of a halved reverberation time can be achieved in the majority of the octave bands. The proposed measures for the larger production hall would not lead to the objective being fully met, but further measures would need to be implemented. Consideration of the cultural value of the glass factory justifies that a longer reverberation time can be accepted.

Reverb är en effekt brukad inom bland annat musikproduktion för att mixa ljud, som flitigt används och är universellt erkänd som ett väsentligt verktyg. Däremot, inom domänen för röstinspelningar -framförallt radio och podcasts- är användningen av reverb mer begränsad, om inte obefintlig. Hur lyssnaren upplever en inspelning påverkas av efterklangen tillhörande den inspelningen. Alltså upplevs en lång efterklang tillhöra ett stort rum, medan ett mer dämpat ljud med en kort efterklang upplevs som ett litet rum. Ett nyhetsreportage som påminner om akustiken i en kyrka eller för den delen en inspelning i stil av en podcast -utan efterklang- kan upplevas svårt att lyssna på, framförallt med isolerande hörlurar. Många studier har publicerats om konceptet personligt föredragen efterklang för musik, men få finns för talad röst. Därför genomfördes denna studie med avsikt att hitta en konsensus mellan oberoende deltagare. Vilken efterklangstid föredras vid lyssning till en nyhetsrapport? Varje deltagare i studien lyssnade på sju versioner av en och samma röstinspelning i stilen av ett nyhetsreportage. Varianterna hade olika långa efterklangstider, från 0 ms till 800 ms. Därefter betygssatte deltagaren varje version av ljudklippet på en skala från 1 till 100, motsvarande hur nära inspelningen var till en perfekt lyssningsupplevelse enligt deras personliga preferens. Den extraherade datan från undersökningen indikerar en preferens mot lägre efterklangstider för det givna stimulit. Skillnaden mellan lägre efterklangstider visade sig vara mer signifikanta gentemot motsvarande intervall för längre efterklangstider. Den förväntade toppen för preferensbetygen mellan 200 och 400 ms kunde inte finnas, men avsaknaden av den kan till en del förklaras av flera faktorer, såsom: en skiljaktighet mellan ljudklippets och reverbets kvalitet, omfattningen av studien eller det faktum att ett träningsmoment saknades innan studiens start. / The reverb effect in the world of music production is frequently used and universally regarded as an essential tool. On the other hand in the domain of speech recordings -primarily radio and podcasts- is the use of reverberation more limited if even used at all. How the listener percieves a recording is affected by the reverberation of said recording. More precisely, a long reververation can be percieved as belonging to a large room, while a more damped sound with shorter reverberation sounds like a small room. A news broadcast sounding similar to church acoustics or a recording in the style of a podcast -with no room response- can be difficult to listen to, especially for a listener with isolating headphones. Many research articles and studies have been published about the concept of personally preferred reverberation for music, but very few for speech. Therefore this study was conducted with an intent to find a consensus between independent participants. What reverberation time is preferred when listening to a news report? Each participant in the study listened to a set of seven versions of a single voice recording in the style of a news report. The variants had reverberation times spanning from 0 ms up to 800. They then graded the recordings on a scale from 1 through 100 corresponding to how close to an ideal listening experience they had, according to their personal preference. The data extracted from the study points to a preference towards less reverberation time. The difference between smaller reverberation times were shown to be more significant compared to the difference between the same interval at a longer reverberation time. The expected preference-peak at between 200 and 400 ms was not found but the absence of it could be explained by several factors, such as: disparity between the quality of the soundclip and the quality of the reverb effect used, the extent of the study of the lack of a training session for the participants before the start of the study.

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The aim of the diploma thesis was to design the reconstruction of the music hall in the existing building of the private music school D-Music. The building is located in Kromeriz, cadastral area Kromeriz. I emphasize the design from the perspective of acoustics. The thesis also evaluated the noise load from the adjacent road II. class, for design hole fillings. It is a five-storey building with one underground and four above-ground floors. The music hall is located on the first floor and is designed multifunctionaly - for music with mobile acoustic absorbers for speech.

The aim of master‘s project is to design a new building of the office building in the cadastre area of Rohatec. The project is divided into three parts. The first part deals with the design of environment friendly and sustainable building. The second part is focused on the design of building services and the processing of building energy services. The third part is focused on the modeling of the noise study, the assessment of the soundproofing of the external cladding and the assessment of the reverberation time.

Klassrumsakustik behandlar rumsliga förutsättningar för ljudutbredning där god talhörbarhet är av vikt för elevers och lärares välbefinnande och möjligheter till goda lärmiljöer. Även kognitiva förmågor som minnesfunktioner påverkas av ljudmiljöer, där lägre bakgrundsljudnivåer och kortare efterklangstider förordas av forskning och byggnadstekniska standarder. Bakgrundsljudnivåer, efterklangstider T20 och reflexnivåer C50 kan tillsammans ge en bild av en god ljudmiljö för lärande i klassrum. I denna undersökning har fem klassrums ljudmiljöer utvärderats och enkätundersökningar har använts för att undersöka elevers och lärares subjektiva upplevelser av dessa ljudmiljöer under aktuella lektionstillfällen. Det har inte kunnat dras några tydliga korrelationssamband mellan akustiska data och subjektiva upplevelser av ljudmiljön från denna undersökning. Dock har undersökningen erhållit akustiska mätvärden från de aktuella klassrummen och speciellt två av klassrummen har funnits undermåliga i jämförelse med riktvärden från standarder med avseende på efterklangstider. / Classroom acoustics deal with spatial prerequisites for sound propagation, where good speech audibility is important for the well-being of students and teachers and provide opportunities for good learning environments. Cognitive abilities as memory functions are also influenced by sound environments, where lower background noise levels and shorter reverberation times are advocated by research and acoustical performance criteria for classrooms. Background noise levels, reverberation time T20 and room response C50 can together provide a picture of a good sound environment for classroom learning. In this survey, five classroom sound environments have been evaluated and questionnaires have been used to investigate the subjective experiences of pupils and teachers in these sound environments during current investigated lessons. There has been no clear correlation between acoustic data and subjective experiences of the audio environment from this survey. However, the survey has obtained acoustic measurements from the current classrooms and especially two of the classrooms have been found to be substandard in comparison with the guideline values of reverberation time from standards.

One of the mixing engineers most important tool when listening, analyzing and taking decisions is the physical space in which the reproduction system and the monitors are placed. The space needs to fulfill certain aspects to be able to qualify as a control room considered good for taking these decisions. In this study an active listening test was conducted to investigate if the RT60 of the natural reverberation in the room affected a mixing engineers’ decisions when adjusting parameters on an artificial reverb. 16 subjects participated, the subjects adjusted reverb level and reverb time of an artificial reverb in two different acoustical environments, with two different values of RT60. The environments were based on a professional control room made for mixing and mastering. The two values for RT60 was achieved through manipulating the room with diffusors and absorbing material. It was found that the subjects were able to adapt to the different acoustical environments, although other differences were found. The order of the which of the environments the subjects started in and which parameter the subject started adjusting, showed a considerable impact on the result. As well as what kind of factors the subjects considered when adjusting the artificial reverb.

This paper presents parameters of evaluation of acoustic quality of the space. It is divided into parts presenting physical principle of the origin and movement of the acoustic signal, principles of its processing with current technology and properties of the acoustic field. This is followed by an analysis of the musical part and notes on psychoacoustics. The document contains a description of relevant parameters of acoustic spaces and way in which we can reach desired results, including material analysis. The paper mainly focuses on description of relevant parameters of three acoustic spaces which were measured. The last part of the work is a program for elementary acoustical measurement, which can be provided by means of commonly accessible equipment such as a notebook or a personal computer.

Modeling underwater acoustic propagation comes with a variety of challenges due to the need for proper characterization of the environmental conditions. These conditions include ever changing and complex water properties as well as boundary conditions. The BYU underwater acoustics open-air tank test-bed and measurement chain were developed to study underwater acoustic propagation within a controlled environment. It was also developed to provide ways to test and validate ocean models without the high cost associated with obtaining open ocean measurements. However, tank measurements require additional characterization of boundary conditions associated with the walls of the tank which would not be present in an open ocean. The characterization of BYU's underwater acoustic tank included measuring the calibrated impulse response of the tank through frequency deconvolution of sine swept signals in order to determine the frequency dependent reverberation time through reverse Schroeder integration. The reverberation time allows for calculating the frequency dependent spatially averaged acoustic absorption coefficient of the tank enclosure boundaries. The methods used for this study, common to room acoustics, also yield insights into the Schroeder frequency limit of the tank as well as validate models used for quantifying the speed of sound in the tank. The acoustic characterization was validated alongside predicted values and also applied to a tank lined with anechoic panels in order to improve the potential for modeling the tank as a scaled open ocean environment. An initial investigation into effective tank models evaluated the idealized rigid-wall and pressure-release water-air boundary model, a finite-impedance boundary model applying the measured acoustic boundary absorption and a benchmark open ocean model known as ORCA in order to determine potential tank model candidates. This study demonstrates the efficacy of the methodology for underwater acoustic tank characterization, provides a frequency dependent acoustic boundary evaluation from 5-500 kHz, and provides an initial comparison of tank models with applied characterization.