Nachhallzeitenkalkulation in der Raumakustik

Um das Abklingverhalten eines Raumes zu beschreiben, wird der Begriff Nachhallzeit verwendet. Dieses bezeichnet die Zeit, in welcher ein Schallpegel um 60 dB abnimmt, nachdem die Schallquelle abgeschaltet wurde. Die Nachhallzeit ist dabei abhängig von der Raumgröße, der Raumgeometrie und der Oberflächenbeschaffenheit von Wänden, Böden und Decken. Nachhallzeiten verhalten sich im Frequenzspektrum nicht gleich, sondern unterscheiden sich, abhängig vom Oberflächenmaterial von Räumen, teilweise stark. Häufig brauchen tieffrequente Schallanteile länger um abzuklingen als hochfrequente.

Nachhallzeiten können zum einen gemessen, zum anderen aber auch berechnet bzw. simuliert werden, wenn die wesentlichen Variablen bekannt sind.
Zur Berechnung der Nachhallzeit finden in der Praxis zwei Formeln Verwendung. Die Eyring’sche und die Sabine’sche Formel.

Für eine Nachhallzeitenkalkulation nach Eyring wird das Volumen des Raumes V und die gesamte Absorptionsoberfläche A benötigt. Letztere wird durch Addition der einzelnen Absorptionsoberflächen, die sich wiederum aus der Multiplikation der jeweiligen Absorptionsgrade α und der Oberflächengröße der unterschiedlichen Oberflächenmateriale ergibt, berechnet.

Berechnung der gesamten Absorptionsoberfläche

Daraus kann der mittlere Absorptionsgrad α des gesamten Raums berechnet werden. Dafür die gesamte Absorptionsfläche A mit der Gesamtoberfläche des Raumes Sges dividiert.

Berechnung des mittleren Absorptionsgrades

Mit diesen Variablen kann nun die Nachhallzeit nach Eyring berechnet werden. Hinzu kommt die Energiedämpfungskonstante. 4mV beschreibt die Absorption von Schall im Medium Luft. Bei kleinen Räumen und nicht zu hohen Frequenzen ist diese allerdings vernachlässigbar.

Berechnung der Nachhallzeit nach Eyring

Schwach bedämpfte Räume, also Räume mit einem mittleren Absorptionsgrad von α < 0,25 werden mit der vereinfachten Formel von Sabine berechnet.

Berechnung der Nachhallzeit nach Sabine

Die Nachhallzeit wird nun für jedes einzelne Frequenzband (in der Regel Terz- oder Oktavbänder) berechnet, um ein frequenzunabhängiges Verhalten der Nachhallzeit bestimmen zu können. Solche Kalkulationen werden vor allem bei der Planung von Gebäuden insbesondere von Konzerträumen, Tonstudios oder Konferenzräumen benötigt, um richtige Entscheidungen bezüglich der Innenausstattung und der Auskleidung von Oberflächen treffen zu können.


Thesis Evaluation – How digital Developments impact Brand Uniqueness

Title: How digital Developments impact Brand Uniqueness

Subtitle: A Case Study on Personalization and Brand Equity MASTER THESIS

Supervisor: Univ.-Prof. Dr. Oliver KOLL Department of Strategic Management, Marketing and Tourism

University: The University of Innsbruck School of Management

Author: Philipp JUEN, B.A. Innsbruck, May 2019

This thesis has only some similarities to Janina Schindlers and my thesis, but it was the closest I could find. It was done for a Strategic Management, Marketing and Tourism major, not a design-related discipline.

Level of design

The Master-Thesis has a pretty basic, standard design. It’s just done with Microsoft Word and there was clearly no focus on any further aesthetics needed.

Degree of innovation

Since it is a case study it is more of a representation of the state-of-the-art in the year 2019.


Philipp Juen wrote his thesis without company support (he was not paid for it or anything) and without any other team members. There was just the support of his family and his supervisor Univ.-Prof. Dr. Oliver KOLL. In addition, it is clearly visible in the work that the author has given his own thoughts to the researched topic and was thus able to present the connections.

Outline and structure

The work is well structured. Nevertheless, there is a major structural ambiguity. In my opinion I think it is better to place the list of tables, list of figures etc. at the end of the thesis and not in the beginning.

Degree of communication

Basically, the level of communication can be classified as good. Clear definitions of terms are given in the right place. This guides the reader well through the topic. However, there are some chapters in which many visual facts are described that could be made easier to understand with the support of pictures or graphics.

Scope of the work

I consider the total length of 93 pages to be appropriate for a master’s thesis. The topics are presented precisely and comprehensively.

Orthography and accuracy

Spelling as well as grammar, sentence structure etc. are in order. There are no serious errors to be found.


The number of sources used seems appropriate. The ratio of online sources to specialist literature (clear predominance of specialist literature) is also okay. However, the bibliography could be clearer, despite the alphabetical order (e.g. by dividing it into books, journals, etc.).

Thesis Evaluation – Mobile Map Applications Analyse und Evaluation von mobilen Kartendiensten bezüglich Interaction Design und Usability

The master thesis was written to create a catalogue of measures for the app „qando“, a mobile information service of the public transportation provider in Vienna to improve the usability.

Mobile Map Applications –
Analyse und Evaluation von mobilen
Kartendiensten bezüglich Interaction Design und Usability“

University and year of publication
Univerisät Wien, 2014

Level of Design
The design of the work is not really special. It is well organized but the appearance is more like a scientific work and not special designed.

Degree of innovation 
The outcome of the thesis is not an innovation but more a statement about an existing app.

He work is done independence but with the focus on the app “qando”.

Outline and structure
The work is clearly structured and follows a red line. First the current state is defined and also a comparison with another app is done. Afterwards the testing is very well explained and in the end the outcome is written down.

Degree of communication
The structure is clear and easy to understand. The red line is well followed and the different modules with their submodules make the thesis easy to understand.

Scope of the work
It takes 40 pages to talk about qando the first time but then the testing is written in 4 pages. This is a bit short in my opinion and could have been a bit more detailed. But then the outcome is explained very detailed again. In total the work has 131 pages which is quiet a lot.

Orthography and accuracy
Pictures are all explained and sources are named. The language is in German and good, sometimes the sentence are a bit long.

There is a lot of literature uses, some are pretty old (from 1995, 1998) and some newer. There are no internet resources named so it seems like only offline literature is used.

Tilman Franz Harmsen. 2014. 

„Mobile Map Applications –
Analyse und Evaluation von mobilen
Kartendiensten bezüglich Interaction Design und Usability“

Universität Wien

Nine points to IDEAL object

Neri Oxman, material ecology architect, has crystallised her practice’s naturecentric philosophy in a series of principles to which human clients will be asked to commit. The principles have undergone several revisions and are still in flux. The most recent version is “Nine Commandments for a Material Ecology”, that is correlated with design approach, centred not on human beings, but on nature as a part of system. Following those steps, maybe, we will be able to create better design objects, that I called “Ideal” in title, just for better perception. Because Ideal does not exist hehe.

So, the commandments in nevalogue are constructive, a declaration of intent for a new design practice. The early version were descriptive of Oxman’s intellectual process and juxtaposed old and new, considering design before and after digital computation and the advent of a so-called Century of Biology at the turn of the millennium.

Nature as Client

“The natural environment at large constitutes the client for every commissioned project, as well as its site and material sources.”

Okay, this one is hard to implement into product design. Buut, we can try our best to use ecological material and their microstructure, as well as macro. To build structures that respond to the environmental conditions and instead of being more fragile with the flow of time, started to be anti-fragile. What means better or not suffering, at least.

Growth over Assembly

“Nature grows things. We will be able to create objects that will respond to their users, adapt to their environment, and even grow over time after they have been printed”

Comment: this principle conceptually moves design and production into the new age of biology, from the assembly line to the wet lab.

Neri Oxman team already were doing similar project, as Silk Pavilion, where caterpillars weaved the dome under the influence of light. Or the green bridge in Stuttgart.

Integration over Segregation

“The typical facade of building is made up of discrete parts fulfilling distinct functions. Stiff material provide a protective shell, soft material provide comfort and insulation, and – in buildings – transparent materials provide connection to the environment. In contrast, human skin utilises more or less constant material constituents for both barrier functions(small pores, thick skin on our backs) and filtering functions(large pores, thin skin on our face). In an ideal object, barrier and filtering functions are integrated into a single material system that can at any point respond and adapt to its enironment.

Comment: Oxman often describes her work as noncompositional, a whole in which the same material articulates dynamically the required functions.

Non-Human-Centered Design

“The group considers all living creatures as equals.” What is quite common in modern world and modern design approach. People start to make non-human-centered design to save ability to adapt to environment, not destroy it and create the new one. “The group aims to shift human-centric design to a design culture focused on conserving, improving and augmenting the natural environment though novel technological developments.”

Comment: The past decade has seen an increasing preoccupation with interspecies design and questioning of anthropocentric values, and Oxmans new practice chooses this position as its baseline.

Difference over Repetition

“Industrial products generated out of machines consist of repeatable parts with identical properties. Comprehending difference enables us to design repetitive systems — like bone tissue — that can vary their properties according to environmental constraints. As a consequence of this new approach we will be able to design behaviour rather then form.”

Comments: the form-giving design of yesteryear yields to the new concept of formation, in which a system adapts and performs — behaves.

Decay or Disposal

“The Practice implements design workflows in which matters is synthesised systems, and consumed by the same ecosystem upon obsolescence. Designed decay is the process by which matter is programmed to rejoin an ecosystems resource cycle and fuel new growth”.

For example, forest eco-system is working in this way. When the old tree is dying, it gives live for couple of new ones, for some mushrooms and batteries around. And the cycle repeats.

Comments: An embrace of circularity, this principle affirms the role of the architect within the ecosystem.

Activist Design

“Any design commission becomes associated with a particular technology, invented or improved upon by the Lab, which embodies the value system associated with the group, and is directly linked to design and construction processes relevant to the commission.”

Comments: Several enterprises, nonprofit and for-profit, are currently trying to integrate ethics and social and environmental responsibility into their practices, and to pass there values on to their customers — a brand of activism from within the system. Oxman’s group will use technology as a vessel for change.

Some of the companies are adjust ethics to their policies, and not vice versa. The desire to cheat and deceive disappears, when we put our skin in the game(reference to the Inu Anum sîrum).

System Over Object

“The product – be it a product, a wearable device, or a building – is considered part of a system of interrelations between natural and designed environments including interactions between the entity and the human body as well as the entity and its environment.”

The world as the fascial human body, where all elements consist from similar material, but in different proportion it gives absolute different result.

Technology over Typology

“Moving from the taxonomic classification commonly found in buildings and urban places… topology – the way in which constituent parts are interrelated or arranged – is the driving force behind the design process, promoting condition-based programming as the approach for organising spaces and making places.”

Or to be fragile or anti-fragile?

Thesis Evaluation – Mobile Applikationen in der orthopädischen Rehabilitation

The master thesis was written in cooperation with a fitness start-up in Graz and aims to show how several problems can be solved in and after orthopaedic rehabilitation with the help of a fitness and health app (Kendlbacher 2019, 8).

Mobile Applikationen in der orthopädischen Rehabilitation

University and year of publication
Karl Franzens University Graz, 2019

Level of Design
The design of the work itself is structured but no importance was given to making it look appealing – whether colours, additional illustrations, etc. The design of the app (the outcome) is not up to date and is confusing.

Degree of innovation 
The idea behind a fitness app is nothing new, but the requirements within the app are different, which can increase the degree of innovation. To what extent, I cannot judge.

She wrote her thesis with the support of a start-up in Graz.

Outline and structure
She has worked hard on the topic, which is clearly noticeable. She has structured and organised her work into several sections. The work is clearly structured and the division is logical.

Degree of communication
It is clearly and simply structured. The author makes it clear what the thesis is about. 

Scope of the work
The thesis has 76 pages. The scope of the work is large in terms of research, but the design of the app (the final product) is clearly lacking. Unfortunately, the app was not realised but a low fidelity prototype was created and the section describing the app is very small and briefly formulated.

Orthography and accuracy
The work is error-free in spelling and comma placement. The language is good. All sources have always been cited. Abbreviations have been marked with a number and described in more detail at the bottom of the page.

The literature varies greatly between years of publication. The paper was published in 2019, there are two sources published in the same year (6 pages of bibliography). 

Kendlbacher, Julia. 2019. Mobile Applikationen in der orthopädischen Rehabilitation. Graz: Karl-Franzens-Universität Graz, 2019

Thesis Evaluation- Sonifying Air Quality: Investigating Musicality and Aesthetics in Data Sonification

The following thesis actually comes from one of the universities that I was considering when I was looking for a Master’s programme. I thought it would be interesting to take a dive into what their students did and kind of compare with FH Joanneum.

Author: Olli Ketonen

University: Alto University, School of Arts, Design and Architecture

Country and date: Finland, 2021

I chose this topic because my interest was piqued after realising this thesis offers a more artistic/creative approach to data sonification than I have seen before. The degree seems to be similar to that of FH Joanneum.

Level of design

The final product seems to match the initial expectations of the thesis. The author provided good detail regarding the building process itself.

Degree of innovation

Sonification has been done a lot before, and I believe there was already sonified air quality data before this thesis, however the author decided to expand on an existing subject and add to it in a creative way. He mentioned how unexplored the aesthetic aspects of sonification are. The final product is very unique (data sculpture).


Based only on the thesis text, I would say the author worked mostly independently. I did not see him mention that he asked someone for help in the research. He did, however have a 3D modeller design the sonic sculpture, but according to the Author’s own specifications backed up by research in the thesis.

Outline and structure

Based on Aalto’s own formatting guidelines, this thesis seems to be properly structured. There is tons of graphs that make it easier to read, however I would love it if there were more illustrations that depict the author’s journalling process and the ideas in his head.

Degree of communication

To me personally it was clear, but I am afraid that someone who has no previous experience with air sonification doesn’t know the different abbreviations in the air quality data table. There were some other abbreviations here and there that might be unknown to non-sound designers.

Other than that, the work was explained in great details, with pictures showing what the author meant. He made sure to make the sketches as simple as possible, including only the essential information. he explained all the basics of sonification, so no previous knowledge is necessary to understand the thesis.

Scope of the work
The work was 60 pages long + 3 pages of an interview transcript. I thought that was a really nice touch and the amount of information/graphics was just right for a master thesis.

Orthography and accuracy

I did not spot any grammar or syntax errors. Data also seemed to be well backed up and the air quality tracking information was obviously archived meticulously.


There was a very big amount of literature at the end, 85% being specialised books and articles. Only a few sources were online posts or unspecialised articles.

Kritischer Bewertung einer Masterthesis – Digital Simulation and Recreation of a Vacuum Tube Guitar Amp

Title: Digital Simulation and Recreation of a Vacuum Tube Guitar Amp 

Author: John Ragland

Academic degree: Degree of Master of Science 

Place & date: Auburn, Alabama, May 2, 2020 

I chose this work, because it could be a relevant thesis to the topic I might want to address in my Master thesis.

Level of design

The design level of this work is quite good. The lists and the standardization of the structure make the work really easy to read and understand.

Degree of innovation

While it’s a pretty cool theme, it’s not that innovative. It is a field that has been studied before, and although the model he has chosen to recreate is quite interesting, it has already been done. However, the results are positive and important for this field.


It is not so easy to assess its independence. Since it is only practical / technical work and the author had to do everything himself (and of course with the help and suggestion of the tutors) I would say that he is quite independent.

Outline and structure

This work is well structured, everything is clear and it is easy to scroll through the pages. There is just a bit of confusion in the structure of the index, where sometimes the chapters are written not in the right chronological order, and this bothers me a little.

Degree of communication

It is really clear. The list of abbreviations at the beginning of the work makes everything immediately clear. Explaining all the terms in the beginning helps a lot to avoid wasting time looking for them somewhere in the text.

I think that even those who are not an expert could follow this work and understand it (even if not 100%, due to a technical / specific mathematical procedure). The support of images and diagrams helps a lot to visualize the whole process.

Scope of the work

The work is about 48 pages. I would consider it a bit too short for a master thesis. The process is really well explained, but perhaps some theoretical themes or previous work could have been described in more depth.

Orthography and accuracy

Except for some space or quotation mark errors, there are no grammatical errors. The sentence structure is also well done.


I would say there is a good amount of literature. Most of them are not online sources and all are specialist publications.

Evaluation of Thesis “Material-based Design Computation” by Neri Oxman

Level of design

The doctor thesis has the layout of the philosophical work, academic framework and as an experimental practice. In the thesis author faces intellectual and technical challenges, as well as with theoretical framework. Design, in this case, is the combination of prosthetic device design and product design in general. Despite the fact that idea is crossing the borders of the design definition and incline more in technological aspects, it is still the art experiment. Maybe, even more it was before.

Degree of innovation

As I mentioned in previous paragraph, the borders of design erasing in this work. Author is experimenting with forms, techniques and ways to product. Everything is described in detailed and step-by-step way, plus comparing things between each other.


The work itself is the independent research, that is made on the base of other people work, opinion, educational level, comments and help. Author mentioned all the people and educational institutions, museums and groups, that inspired her during her life, work and this particular thesis. Since such work is quite extensive and necessarily requires help from the side.

Outline and structure

Structure is divided into nine main parts: pores of the synthesis of material form, where the material-based computation, form and structure are described; nature’s way from micro to macro organisms; the new materiality or the influence of form, how it changed and current problems; design computation; material-based design computation; natural artifice — natural design in new way with the reference to form again, but from the nature angle; natural fabrication; contributions.

All modules are supported with explanation, examples and authors own experiments.

Degree of communication

Communication is clear and easy structured. Modules are presented as modules with sub-modules, what makes orientation fast and whole topic understandable. Experimental designs employing suggested theoretical and technical frameworks, methods and techniques are presented, discussed and demonstrated.

Scope of the work

Huge. Research from different side, with all possible and impossible materials, graphs, digital models, that clearly demonstrates the work done. Design experiments shows the contribution and the potential future of a modern design structure and future research field.

Orthography and accuracy

I would say, that accuracy is on a high level. As I mentioned, the whole thesis is described in precise manner, so person, that is outside the topic, can understand.


Author is referring to 389 resources. Most of them are from the engineering, biology and architecture spheres. Neri is using the computation methods work, more philosophical works, as “Design and Elastic Mind” or “The Ideas of Biology”, surface structure and resources, combining both technology and biology.

Focusing on MA-thesis part II – conversation with Gabriele Lechner

Today I had a meeting with Gabriele Lechner from Werbelechner to get input for my planned master thesis.

After thinking more about how to approach the thesis I came up with the idea that I would rather focus on analog products, but still outlining digital tools and approaches, as nowadays analog products are often based on digital data. Therefore I explained the project as followed:

My work deals with analog media, conquering with digital media. For this my thesis gives an insight in media theory and history, dealing with the specific characteritics of both representation systems. Besides, analog and digital processes and methods, various media and formats will be described to give basic information on all analog and all digital but also hybrid forms of media and their design. For the practical part an analog product based on digital data based on analog ideas is planned.

Gabriele Lechner mentioned that I should be more focused on the general method and a concrete practical piece for the thesis than on a wide range of content.

The conversation was very constructive, helping me to outline the structure for my thesis in a better way: the theoretical part can be followed by examples of use in film, sound, graphic design and photography. To get interesting content it would be good to find experts in the field and ask them for an interview. The results of the interviews will help to outline not only aesthetic and technical characteristics of d+a media, but also in means of range and scope, quality and aspects of perception. The practical workpiece could be the printed master thesis – the book can feature various papers and analog production methods to underline the theoretical findings.

Refugees and local people in host countries

I started my thesis research on the refugee’s problem and tried to go with designing an educational platform that can facilitate their educational challenges but when I went further with this idea I found it needs professional skills in psychology and educating, so I changed my way to work on the communicating problems so I did researches and also meet with refugees and a guy who was responsible for the young center which offered free programs and snacks to youngsters including refugees during the summer, I came to a conclusion of what I did till now so I found that there is a big gap between these two groups of people,

and what I want to do as an interaction designer is to bridge these gaps.

At this point, one of my colleagues and I decide to do the project together but with divided tasks, she will do the practical and technological part and I will do the theoretical part and do the researches, as the start point we did some brainstorming about what the gaps might be and did the short questionnaire, in this questionnaire, we categorized the gaps caused to cultural, lingual, … .

We will analyze the data in this step and I will plan to do some interviews with the refugees.