• Son Luu

Echo of Silence

Updated: Dec 24, 2019

Class: Light as a Medium of Art: Ways of Seeing Now

Instructor: James Clar


In a world that is getting noisier with the excessive use of machines, what does uninterrupted silence sound like?

A clear box hung from the ceiling, containing a standing bell that sings an intriguing, yet meditative, calming sound, amplified by the box itself every time a solenoid creates a mechanical pulse. But at times, the lights would turn off and all mechanical movements cease. What controls these interactivities?

Standing bells are used for religious purposes, music making and meditation, as well as healing for personal well-being. The humble instrument sends us - humans of the digital age, a message about the underappreciated power of uninterrupted silence. The sculpture’s activity is designed to respond to room noise level as the only interactive mechanism with its audience.

‘Echo of Silence’ is the gift of feeling more connected to our surroundings and to other humans in a common physical space when we are tuning in and listening closely to ourselves, to others and the world around us in the age of constant digital distractions. How can we ‘listen’, more and better, to create new ways of being and acting together, to better engage with our environments and one another amid our ‘noisy’ everyday life?

Primary Tools: TouchDesigner - serial communication with Arduino, DMX control and audio analysis

Role: ideation, concept development, technical testing, prototyping, fabrication


Echo of Silence is my third and last light installation for Light as a Medium of Art. Throughout the process of exploring the history and various processes of light art from experts in the field, I've learned that light, a long-term established aesthetic means of art, can be a powerful tool to express ideas and inspirations, far beyond something that's just visually stimulating . There are light forms that look spectacular, bringing those 'wow moments' to the audience, and then others that bring the 'aha moments' because they are meant to send a message, an idea, a feeling. 'Echo of Silence falls into the later category.

It was a pleasure to collaborate with my talented friend, Nick Zhang. The idea we were both inspired to explore and think deeply about, came from the times we felt more connected to ourselves, to the people around us, to our environment when we take a second to listen more closely. Listening: one might think it is an old concept, which may be true to certain extent, but how come we felt such a strong connection and relevance to our time and the things we do on a daily basis? I suddenly realized that, as technology students, we are constant 'makers'. We make machines, and/or we make stuff with machines. The moving and talking machines excite us, and many other people. When not making, we play with other digital technologies and personal devices. Until one day, we might have felt we have become so much better at listening and talking to digital machines, than listening and talking to humans, to nature, and even more importantly sometimes, to ourselves.

The things that we all seem to pass by so many times, and never pay attention to them, because they don't play sound or display flashing lights [like those LCD screens] may have layers of interesting stories and insights that we will never find out because we don't have time to listen to what they have to reveal to us. People that are in the same common physical space with us may have so many interesting stories to share, but we simply don't have enough interest to take a moment to connect with them, because we keep getting better at listening to digital machines, not humans. Nature may be crying out loud for help, but we may be tuned out from our environment.


Sketch, sketch, sketch...

We went through many ideas while sketching, asking who we want to be our target audience, what they would want to see, how the sculpture should look like, what the interactivity should be, based on what mechanism, how much interactivity we want, where it would sit or display...

Sketching the ideas out helped reveal the potential challenges that may come with each of the ideas, and helped us evaluate which approach may work best for the timeline and resources available. In addition, we were also able to decide which approach would best highlight the concept and idea behind.

We thought of different objects to incorporate into the sculpture, including tuning folks which Nick came up with, which we decided to save for our next project.

Collaborating with Nick taught me so many things about interesting sound and music instruments and tools used in music making. I was inspired when we landed on using a standing bell, or "singing bowl" [as some people would call the object]. The bowl-shaped object that I have only seen being used for religious purposes can be used in other meaningful interactions with humans, such as a music instrument, a meditation tool with healing power for personal health. And, just like that, I became to know much more about the interesting object, just from taking the time to connect with it, learn about it, listen to it.

Overall Sculpture Form

Overall description: a kinetic sculpture, consists of a clear box hung from the ceiling, containing lighting equipment and kinetic components that are activated only in silent or low noise-leveled environment.

Components: LED lights, a fixed tuning fork and a solenoid.

How it works: Noise level is constantly measured and analyzed in real time against a pre-set threshold. Above the noise threshold, the kinetic sculpture pauses all of its activities (lights switches off and all movements stop). As noise level returns to below the threshold, the lights turn back on; the solenoid starts generating timely mechanic pulses against the tuning fork to create a long, echoing sound, amplified by the box itself.

For about a minute long, viewers feel more connected to the environment and the humans around them in a common physical space, while listening closely to the intriguing, yet meditative, echoing sound generated by the tuning fork.

Technical Testing - Prototyping

Part of the prototyping process, we conducted several technical tests on different components in order to decide the most appropriate technical design for the sculpture.

Test 1: Controlling solenoid with Arduino

Test 2: Switching to a bigger solenoid to provide more force (on a tuning fork)

When we conducted this test, we were still considering using a tuning fork for the sculpture. This was a key test for us to decide not to continue with using a tuning fork for the project. The surface of the tuning fork was so narrow that it would require perfect positioning of the solenoid for it to strike at the perfect angle, at the correct spot every time in order to effectively make an echoing sound. To do this, we would need to design a fixed and very precise holding bases for all the components. With the time allowed to get the project moving forward, we decide to explore other sound making objects. This was when our standing bell (or singing bowl) became the perfect alternative.

While using a bigger sized solenoid which uses 12V AC current, so we needed to use a 5V-12V relay to convert high voltage AC to low voltage DC and connect it to 5V Arduino.

Test 3: TouchDesigner sending 0 and 1 data to Arduino via serial communication to turn on/off solenoid

Nick has worked with audio analysis in TouchDesigner, and I have worked with DMX control in TouchDesigner, but the only thing we have not had experience in is serial communication with Arduino in TouchDesigner.

The challenge with this test is that the documentation available for TouchDesigner for serial communication was only for sending data from Arduino into TouchDesigner. The other way around was very limited in documentation, so this was a bit of a challenge. We finally figured it out, but there was still a lot of work to be done.

Test 4: Combining TouchDesigner audio analysis to control both solenoid (via serial communication with Arduino) and LED lights (via DMX control)

At this point, we were able to combine everything together to put TouchDesigner audio analysis to a test for controlling the solenoid and LED lights at the same time. It was very glitchy and required many more rounds of tweaking the codes and testing over and over again.

There were many more tests we had to conduct, which resulted into many reiterations of the code, the audio analysis, affected many versions of structural design of the sculpture. But the above tests were some of the key tests that led to many decisions going forward.

Some other components that were used for DMX control and communicating with TouchDesigner to send data to LEDs include Enttec DMX Pro and a DMX512 decoder.


As part of the fabrication of the sculpture, we tested many options of materials to be used. Some of the key materials are:

- Standing bell: the echoing sound is intriguing and rewarding at the same time. It is a humble instrument, and one must tune in to realize the seemingly ordinary bowl-shape object has a hidden power of healing.

- An acrylic box: as the container for all the components. The box represents a chamber of hidden treasures and stories that one may be curious enough to open and see what is inside. We decided to use acrylic instead of glass in order to reduce the weight of the box, and also increase safety when fabricating and handling the sculpture.

- Two-way mirror: to provide the effect of not being to see through unless a light source comes on from the inside. A layer of two-way mirror will be added to every side of the box. Two-way mirror surfaces only reveal what is inside the box, which is also when we are quiet and listen closely, because only when we actually listen, we can hear stories of the humans next to us, in our lives. They come from all walks of life with interesting insightful stories to tell us but only if we’re genuinely interested in connecting with them.

- Added pieces of reflective mirror: reflecting light and image of the standing bell, reminding us quiet moments of reflection of our own voices can offer revelation of new and fresh directions, ideas, thoughts.

Next, we needed to solder all electrical wiring and components.

Final Product

After weeks of hard work and overcoming so many technical and design challenges, we were very proud to be able to complete and share the story of Echo of Silence to other classmates and the audience at the 2019 ITP Winter Show.

Here are some of our favorite moments seeing the audience experiencing Echo of Silence.

It was more than exciting to see how differently the audience reacted to the sculpture, listen to what they think, feel and relate to.

We asked our audience to write down a few words or sketch something that came to their minds as they experienced Echo of Silence. Here are the sticky notes we collected at the end.

Some of the written words include: 'listen', 'a misty lake at sunrise', 'beginning', 'groundedness', 'secrets'.


Working on Echo of Silence, for me, was an experience and journey in itself.

1. "From concept to execution"

Concept development is never easy, but the journey to arrive at something that both my project partner and I could relate to, feel strongly about so that we both felt inspired to take on the challenge was so crucial. It took us some time to think through, had several discussions with each other and others to finally decide on a concept we were both happy about and felt passionate about making it happen.

Execution is a whole other level of complication after we decided on a concept. This step asks for the making of a "critical object" where the concept and the relevant meanings need to be wrapped around an object that not only make sense to us, but also to the audience in both physical form and conceptual implications.

2. Technical Challenges

As an idea is formed, and the different options for shape and size and design of the object to be created are being consider, technical testing comes right in place to challenge the feasibility of the execution process.

There are many different ways to execute an idea from a technical standpoint. We decided to choose the approach we did primarily based on: what we may or may not have worked with it before, the learning curve for things that we may not have the knowledge of and are required to quickly learn and test, what new technical knowledge we would like to learn and challenge ourselves with, project schedule, the cost involved.

Using TouchDesigner and serial communication was one of the biggest challenges: stability of serial communication with the solenoid operating mechanism remains to go through more testing.

Audio analysis: which can also be done with just Arduino was something we decided to use TouchDesigner due to its flexibility to set different type of analysis, for different types of sound, and threshold ranges. The range need to be tested and may require re-adjustment for different environments depending on the noise levels specific in certain specific settings.

DMX control in TouchDesigner worked relatively stable. However, LED color adjustments for addressable LEDs can be tricky and can sometimes be unreliable. This may have to do with the quality of the LED strips, power supply for the LEDs, or the use of many components in between (such as DMX voltage controller) etc.

3. Materials and Fabrication

Handling acrylic material can be tricky as it is easier to cause scratches and finger-prints during fabrication, staging and installation. However, it was the best material to be light-weight while providing sufficient sturdiness and thus safety during fabrication and installation.

Running long electric wires through several components added more time and resistance to electric current. As a result, responsiveness of electric components was delayed when data is sent from TouchDesigner to Arduino.

Other materials such as two-way mirror, or regular mirror can be tricky due to different visual effects they create. They require testing ahead of time in order to evaluate the resulted effects that may or may not expected.

4. Collaboration and Learning

As a collaborative project, knowing each of our strengths and weaknesses to learn from and help one another was crucial, but opening to listen and learn about each other's personal background, our upbringing stories, cultures, and experiences we've been through was even more significant to my learning and growing throughout this production project. I appreciated our exchanges of cultural and conceptual discussions which inspired us both to create a successful collaboration.

This also echoes the inspiration for Echo of Silence: "listening". Only when we're tuning in and listening closely to ourselves, others and our surroundings will we get to learn, to hear and see the interesting things that we don't normally do, and to better connect with the people and the environment around us, so that we can create better ways of being and acting together in the future.