ASSIGNMENT 1

St. Jakobs Church

The church is deconsecrated and no longer serves as a traditional place of worship. Instead, it functions as a versatile space used for a variety of purposes such as meetings, co-working sessions, conferences, prayer groups, dance events… 

The church has a central nave with a side aisle on the right and a separate room on the left that can be accessed through a door. The apse features a staircase, and an organ is located in this space. The side area is divided into two levels, creating a balcony-like space. The ceiling is circular in shape, with multiple domes extending outward from it. Above the apse, there is another dome. Before entering the main hall, there is a foyer connected to a small exterior porch, which leads to the adjacent square.

Acoustically, it is noteworthy due to its reverberant nature. This quality can enhance musical performances like organ concerts, making the sound rich and immersive. However, the same reverberation can be a drawback during conferences or speeches, as it makes spoken words hard to understand and creates an echo-heavy environment. These contrasting acoustic behaviors create entirely different atmospheres, depending on the use of the space.

The reverberation in the church gives the space a grand, almost spiritual feeling when music is played, like the sound swells and surrounds you from every direction. However, during conferences or when people are speaking, the echo can make it hard to focus, with sounds bouncing back at you from different parts of the room. It feels like the space is too “live” for spoken words to land clearly, and that can be distracting.

List of Acoustic Events and Sources

• Inside the Church (Daytime):
  • Reverberating voices
  • Passing tram noise from outside
  • Coughing
  • The sound of pens tapping
  • Chairs moving
  • Cars from outside
  • Sounds from outside generally enter from the rear, while voices are primarily heard from the front, and coughs come from the left side.
• Inside the Church (When Organ is being played):
  • Organ music
  • Background noises from people moving or shifting around

Acoustic Terminology (Adjectives)

Live: The church hall is highly reverberant, causing sounds to echo and linger throughout the space, especially during music performances.
Reverb-y: The space has a significant amount of reverberation, with sounds continuing to resonate after they are produced
Boomy: Lower frequencies, particularly from the organ, resonate strongly, creating a deep, powerful sound that fills the hall.
Cavernous: The large volume and domed ceilings give the space an expansive acoustic quality, making sounds feel vast and echoing.
Resonant: Certain frequencies, resonate more strongly, emphasizing specific tones like voices or organ notes.

Square in front of the St. Jakobs Church

This public square serves as a resting spot or a passageway between the surrounding streets. It lies between a block of buildings, St. Jakobs Church and two streets. It is accessible by foot and if needed by car. Many people pass through this area when coming from the nearby tram station or as they head towards the church entrance.

The square has a trapezoidal shape, surrounded by trees, with mineral pavement covering most of the surface. A central green area connects the square to the church. This green element, elevated 60 cm above the pavement, is also used as seating. On one short side of the trapezoid is the church, while the other side faces a busy tram stop.

Acoustically it is interesting because of the variety of sounds that can be heard simultaneously. It is a dynamic space where you can hear people talking, the sound of trams, noises coming from the church, bells ringing, and even pigeons taking flight. The complexity of these overlapping sounds makes it an intriguing place from an acoustic perspective.

The square is alive with a mix of urban and natural sounds. There’s the constant noise from trams and traffic from the nearby road, but you also hear the fluttering of pigeons, the ringing of church bells, and snippets of conversations from people passing by. It’s a space where multiple soundscapes coexist, and it feels vibrant and energetic because of that. You’re never in complete silence, but there’s a flow to the sound that keeps it interesting.

List of Acoustic Events and Sources

• Church bells
• Footsteps of people walking
• Conversations
• Tram noise
• Cars
• Someone moving objects around
• The sound of paper being unwrapped
• Pigeons flying off
• Suitcases being rolled across the mineral pavement

Acoustic Terminology (Adjectives)

Busy: The square has an intricate soundscape, with overlapping sounds from people, trams, and the nearby traffic, creating a dense sonic environment.
Open: Despite the surrounding noise, the square feels acoustically spacious, with sounds from the environment blending naturally without confinement.
Crisp: Individual sounds, like footsteps and conversations, are clearly defined, especially in contrast to the background hum of traffic and trams.

ASSIGNMENT 2

For this exercise, I decided to choose a room in my flat at two different times and situations. It was renovated a few years ago, including the windows, and is on the 4th floor of a building. It is on a side street, but close to the motorway entrance and a busy road. 
This means that when the windows are acoustically closed, there is no connection to the outside environment, while when they are open, or when you are on the terrace, the sounds of the neighbourhood are loud. 
I decided to listen to the sounds in my room with all the windows closed and then with the windows open, because I found it interesting to hear the difference in the same room in two different situations. 

Sounds with the windows closed: 

• My flat mate working (pen writing, papers, chair moving, footsteps moving around the flat). Sounds also accompanied by different vibrations, e.g. floor;
• Washing machine;
• People in the stairwell going to their flats;
• Ground floor front door closing.

When there are no such events, the apartment is in total silence, a situation that is sometimes pleasant, sometimes almost unpleasant. 

In all cases, the sounds that can be heard are those produced by people, their movements and their activities. 

When the windows are open, the following sounds are added 

• Cars;
• Trucks;
• People talking;
• Bicycles stopping/moving;
• People working in the street.

These are always man-made. Natural sounds are very faint or absent. During the day of observation the weather was fine, if the weather conditions had been different (rain/strong wind/…) it would have influenced the analysis. 

It is interesting to compare the emotional response and human perception in the two situations. When the windows are closed and there is silence, the smallest changes are perceived much more and affect the emotions more, especially in alarming situations. If a child is running down the stairs, my attention is focused on that. Or if there is a piece of metal in the washing machine and it keeps hitting the machine, my attention is immediately drawn to that sound. 
On the other hand, if the situation is very quiet and there is almost no sound, I hear a very quiet frequency/sound. I would almost say I hear silence – difficult to describe. This can be pleasant, but sometimes strange, because what you hear most are the sounds of your own body. I often prefer to put on some background music in these situations. 
When I open the windows, everything changes. There is a very dominant background sound, and then everything that is happening in the flat fades into the background. You can hear the cars, like a stream coming from the motorway, which does not bother you because it is constant. What affects me most emotionally are the cars that pass by one by one, and even if it is just for a short moment, the sound they make is dominant and attracts my attention and disturbs me. 
However, I have noticed that when I live in this flat, I choose which sound environment I prefer according to my emotional state. For example, at night I like to close the window to be quiet, but then some mornings I like to wake up and hear the sounds coming from outside, while others I like to remain silent for longer. 
The same happens when I have to work, sometimes I prefer to work in total silence, sometimes I like to have a background sound from the city. 

ASSIGNMENT 3

30dB decrease takes 0.22 sec. RT60 = 0.22 (sec) x 2 = 0.44 sec

No echoes are visible on the picture.

The reverberation Time without abs. at 500 Hz = 2.1, while at 1000 Hz = 2.2.
The reverberation Time with abs. at 500 Hz = 0.3, at 1000 Hz is it almost the same, 0. 28 ca.

ASSIGNMENT 4

I went back to Stauffacher Church, as it’s the space that intrigues me most acoustically, especially considering its potential for improvement.

Right now, there aren’t any significant absorbers in the space. The only absorptive elements are the chairs and people present—factors that aren’t fixed and vary depending on the event.

The building is primarily made of materials with low absorption coefficients that mostly reflect sound. The main materials here are plaster, wood, and glass. For the church’s primary function, these reflective qualities are actually beneficial: when the organ is played, the sound is amplified and clearly heard throughout most of the space. The wood and glass are especially reflective, but I believe it’s primarily the building’s geometry that enhances the wide diffusion of sound. The domes appear to be coated with plaster, though likely only in a thin layer.

The challenge arises when the church is used for gatherings, discussions, or other activities that produce different frequencies and sound qualities from various points in the space.

This situation presents an interesting case study, as the space demands different acoustic qualities depending on the event. A flexible, layered system that could be adapted easily might be ideal. I could imagine adding furnishings that encourage diffuse reflection, like curtains on the ground floor, or elements with high absorption coefficients, that can be moved. If activities are primarily on the ground floor, the first floor could also be used to place these absorptive elements.

With a more detailed study of the space’s usage and sound propagation, we might identify plaster walls that could be adjusted for improved absorption. However, I’d avoid altering the concave surfaces, as they seem crucial for sound propagation, particularly when the organ is played.

Landscape acoustic

As object I choose the window in my room, as it plays a main role for the use and quality of the room.

As I can not bring the object on place, I did a second recording, of a sound I often reproduce in my room: the striking of a match.