Technical analysis of existing solutions for the creation of sonification tools
Technical analysis of existing solutions to selection of the most cost-effective and sustainable tools and materials for the creation of sonification tools. For an effective and interactive class that will allow students to be interested and inspired, and for teachers to be able to guide a sonification class, we had to look into all the hardware and software tools available and their effectiveness, availability, cost, and the ability to promote important digital and technological skills and the enhancement of the digital readiness of the involved schools. Our project stands out from similar educational projects because we combine the programming skills with electronics in order to produce data sets in real-time and build interactive digital systems that receive data through sensors and express them as particular sounds. For example data received from the classroom environment, or the school area. This is made possible when we use microcontrollers to control sensors and feed their data into softwares or even sonify them through the microcontrollers itself.
Software
There is a vast choice of software that can be used for the sonification of data both in real-time and “a posteriori”..
Although the teachers and students have the choice to choose what software to use, we recommend using online software when possible, especially in the case of short duration courses because it usually saves the time of having to install additional software for each student. In the vast field of audio softwares online some of them are more sonification oriented and most have customizable parameters to some degree.
For example MusicaAlgorithms [1] offers the possibility to upload our own data. The drawback is that it assumes that your data will be mapped onto pitch and duration. Allowing your choice on the type of scale and not other aspects like the timbre (what instrument is going to play).
The common and universal MIDI protocol suffices when needed to control custom types of sound and serves as a common format to exchange musical information between audio platforms. Despite some great tools being available like libraries based on programming languages such as python (for example Sonecules[2] or MIDItime [3]) and dedicated software (ex. SonicPi, Pure Data). We choose to use the TwoTone [4] software. It is free to use, versatile and with a user-friendly interface that allows even beginners with reduced skills in programming and minimal expertise in music and audio, to generate a consistent sonification output.
Hardware
Apart from using computers we also looked into microcontrollers to handle sensors and actuators (ex. leds, motors) to add some hands-on approach to the generation of the data to be sonified, with a DIY attitude that has a greater impact on young students than theoretical books and manuals. And giving priority to low-cost sustainable materials There are many low-cost microcontrollers available on the market (Arduino, BBC micro:bit, Raspberry Pi Pico, ESP32, Teensy, Particle Argon/Boron, etc…)
The most widely used microcontroller is likely the Arduino, which has many different versions and copies due to its open-source nature. Other options include the more complex Raspberry Pi and the more educationally accessible Micro:bit.
We choose the micro:bit because it has some advantages over the other microcontrollers available: the device is programmable with a graphical user interface accessible through an internet browser for free, without the need to create an account; the board already has included several sensors including environmental sensors for light, temperature, magnetism, acceleration and sound, and also a small piezoelectric speaker allowing the students to build interactive digital sonification systems that receive data through sensors in a very short time; the micro:bit can also function as a gateway to more complex projects and act as an interface with other devices through MIDI, USB, Bluetooth, radio and other protocols; There is an official data logging library available for the micro:bit [5] that allows the students to record data over time very easily;
Conclusion
In sum, the Micro:bit microcontroller and the TwoTone software were chosen as the main basic technologies to start working with sonification. The reason is that both provide an interactive and hands-on learning experience for both students and teachers. The Micro:bit is affordable hardware, with many embedded sensors, and it is designed for educational purposes. Its programming environment makecode [6] is easily accessible through any internet browser and can be programmed with the simple Blockly [7] visual code editor and also in Javascript and Python. Also, the micro:bit is already available in most of the partner institutions and schools allowing the students to give them a second life and reducing waste. The free software TwoTone is designed to allow users with little experience to upload data and generate an audio file that is the corresponding sonification. A variety of instruments and musical parameters like scale and tempo can be customised by users. These are the main reasons that made them practical choices for schools. Both can work with various tools, data sets, sound outputs, and complementary devices (including other electronic components and MIDI) allowing students to create and manipulate sound creatively. And always keeping in mind that other tools exist and can be explored and used for particular, or more advanced projects.
References