Final Description of Prototype

In a musical composition there are components that structure the music. How could we, in a

visual, interactive and easy way, teach the building of music? And in the same time let youth use

their creativity to compose their own music?

Different materials have different qualities, like different qualities in music gives different
expression. In a musical piece we often have a mix of these qualities. Even the same melodies
can perceive new and changed if played in other characteristics. Could we show this represented
by physical properties of particular materials?

When we started generating ideas, we were immediately fascinated by the composition of a 

“song” or a “tune”. We knew we wanted to teach our users how a composition is built and what 
parts it is made up of. Additionally, we were interested in looking into the characteristics and 
sounds associated with different materials. So, we decided to combine the two. We decided on 
going for a new type of mixing board, which we called SoundCubed. It is an interactive 
mixing board consisting of three vertical sliders and nine cubes of three different materials. We 
wanted to replace the traditional switches and knobs of a mixing board with something more fun 
and intriguing. The user can pick up the cubes, feel the surface and the weight of the material, and
hopefully feel tempted to place them in a slider. 

Each material has different characteristics and a unique feel, that we wished to transform into 

music. The user can listen to the music that is produced by one cube alone and discover how the
sound variates in the four different “levels” of a slider, or place a cube in each slider and listen to 
how the different sounds work together. The user can mix and match the different cubes and 
discover if some combinations work better than others and if so, which combinations of cubes. 
The point is to make the user discover and understand the installation by using it. We didn’t want 
any instructions; the only obvious thing is that the cubes are to be placed in the sliders. The users can find out of the rest by placing and sliding the cubes. We wished for SoundCubed to be an 
installation where the user gets to explore and learn something about music, all while having fun.

During our development process, we focused on making the interface of our prototype intuitive 

and simple for it to be comprehensible and without needing any explanation for the user to be able
to interact with it. To keep the nine cubes in place when they are not in use, the surface of the 
mixer has an area divided into three sections that allow the user to group the cubes by the type of 
material they are made of. In the central part of the surface of the mixer, the area in which the user
performs the main action of mixing sounds and creating compositions, there are three luminous 
sliders where the cubes can be slided all along. With measurements of 24 cm by 6 cm, the 
dimensions of these sliders are adjusted to the dimensions of the cubes (6 cm by 6 cm) to allow a 
smooth interaction. Due to the four different possibilities in each slider to mix sounds, the 
dimensions of the sliders lengthwise are four times the dimension of the cube.

With the exception of the plastic cubes made of foam, painted in blue and with a glossy finish, the 

cubes were made with the material they represent. The elaboration process varied in each of 
them, the wooden and the metal cubes were made by cutting in the same size a wooden idler or a
steel bar. To contrast the weight of the materials so that the user could also feel the difference 
when holding them, we put stones inside the metal cubes. It was important that all of them have 
space inside for a RFID chip and that one of the sides have a piece of black acrylic to allow an 
easy reading between the sensor and the chip when the cube is placed in the slider. This also 
allows the user to place the correct side of the cube down. The surfaces of the three sliders are 
made with transparent acrylic. To avoid the user from seeing the technology inside the mixer and 
to blur the effect of the LED lights, we opaque the surface of the acrylics with sandpaper and then 
placed a piece of white sheet between the acrylic and the RFID sensors.

As for the exterior appearance, the mixer was made with pieces of wood. Some parts were laser 
cut to create the openings for the speakers and for the “Sound3” title, then these parts were spray 
painted in neutral grey. For a stable mixer with no extra movement when using, an internal 
wooden structure that supports the exterior parts of the prototype was built and assembled 
through screws. With two shelves, this structure also serves as a support for the two speakers and
for all the technology required to operate the mixer. The surface of the mixer has an inclination of 
15 ° for an ergonomic use in which the user can easily reach the cubes from the place they are 
displayed to the sliders.

So how does SoundCubed work from a technical perspective? It all begins with 12 RFID readers, 
divided equally amongst the three sliders. When a block is placed, the RFID tells the Mega 
connected to the sensor which material is placed, which slider slider it’s placed in, as well as 
which step of the slider (1-4). This information is then passed from the Mega to our Raspberry PI, 
the heart of our prototype. On the PI we are running PureData, which helps gives us a tool to play 
simultaneous sound files smoothly. Using a sorting system we play the sound file which 
corresponds to the information sent from the Mega. Using a timer we can play the files so they 
match the beat. When playing the sound files, the PI also sends a signal to the Mega and tells it to
tell the Unos to start their lightshows. By doing the lights this way, we make it possible for the 
lights to be in sync with the beat. There is also a separate Uno, not connected to the PI, that play 
a “breathing” light animation for our logo.

Above: A diagram showing how SoundCubed is set up in terms of components.

When starting the project, we wanted to make a model without rules, allowing the audience to 
explore at their own pace. We also wanted to give the user some new ideas/thoughts when it 
comes to music. All this while maintaining a physical, screenless experience. All in all we believe 
we achieve much of which we aimed for. SoundCubed is a tool of creativity, with no rights or 
wrongs. We also believe it gives the insight to how music can be described by physical properties,
which is one of the things we wanted to teach the users.

The other thing being how music is built up. All of music have a fundament, some kind of rhythm that gives structure to the piece. In addition, a given harmony has a set of chords and notes that sound good together. The harmony build up the music horizontality and vertically, and gives guidance for the melody. The structure of music is complex, bused on a set of rules (rules that of course not need to be followed). But in basic it could be quite simple. This is the other pedagogic value of SoundCubed; it describes the building of music simple, but efficient and clear. With SoundCubed you can compose your own music with guidance from three sliders that represent three of the main components in musics structure: Rhythm, bass/chords and melody.    

One thing we didn’t have time to fix was a system for placing multiple blocks in one slider. 

Originally we implemented a mute function, so the slider would be muted if multiple blocks were 
placed simultaneously. However we decided to change to a randomizer, playing from

random placed blocks, as muting the system would add the rule of not placing more than one 
block. Rules was something we didn’t want. If we were to improve on the model on a later 
occasion, implementing a cool feature here would definitely be a priority. This would add to the 
idea of freedom and exploration, a music sandbox.