During this semester, I was able to learn countless notions that led me to the realization of the first prototype of this instrument.
Despite the difficulties, I was able to narrow down the field of variables and question marks that stand between me and the realization of the final product. Through research and experimentation, I acquired the skills to be able to plan the following steps that separate me from the final goal: the realization of a fully automated Hackbrett.
About the physical construction of the instrument. The next step is to build a support capable of holding the hammers for each string of the instrument. As already demonstrated with the prototype, the aim is to obtain a modular structure that can be customized according to technical and artistic requirements.
From the software point of view, the next step is to create a GUI in Pure Data to control the instrument via OSC (Open Sound Control). As a starting point, I will use the library written by Professor Ritsch, LEMiot[1]:
“Making Computermusic Devices using ESP32x with various sensors and actors is the overall goal for the LEMiot project. Using IoT (Internet of Things) technology to interact in Music Performances and Theatre projects or as sound installations. This library is a firmware framework for controlling LEMiot boards using the library ‘OSC_networking’ as device and WiFi management, parameter storage and additionally a simple user interface with LEDs and buttons. Each board as an incarnation extends these functionalities by integrating additional sensors or actuators. The device can be controlled wirelessly using a special ‘OSC’ protocol. A Configuration Tool with Puredata as also a corresponding Puredata library”
This step will enable me to learn the different techniques for interacting with the instrument and the parameters to be mapped. Moreover, the skills to program my own Networking environment.
Another important step to be taken, is the realization of a functional algorithm for the pitch detection. As discussed in previous chapters, my initial approach involves utilizing zero crossing analysis on each individual set of strings. To accomplish this, I will divide my tasks into two sub-levels: software and hardware:
– regarding the software aspect, I will employ the “~zexy”[2] extension for Pure Data, developed by Professor Johannes Zmölnig. This extension provides valuable examples and resources for pitch detection using zero crossing techniques. By studying these principles, I will gain a solid foundation and understanding. Eventually, I aspire to write my own pitch detection algorithm directly on the microcontroller, allowing for a more streamlined and integrated solution.
– regarding the hardware part, I will use the Calliope-board[3] for the further developments. This board offers several advantageous features, including six microphone inputs and an integrated Mosfet system designed for solenoids. These components encompass all the necessary elements to realize the final product effectively.
The final element that remains is the development and integration of a servo motor system for tuning the instrument. However, I have not yet discovered a suitable approach for this specific purpose. The Hackbrett’s strings are closely spaced, which presents a challenge in independently controlling them. Therefore, our initial step will involve designing a system similar to the one depicted in the provided image /Fig. 1).
[1] Ritsch, Winfried UC / LEMiot library · gitlab, GitLab. Available at: https://git.iem.at/uC/LEMiotLib (Accessed: 16 June 2023).
[2] Pure Data Libraries / Zexy · GITLAB (no date) GitLab. Available at: https://git.iem.at/pd/zexy (Accessed: 16 June 2023).
[3] Ritsch, Winfried IEM development area, Sign in · GitLab. Available at: https://git.iem.at/ritsch/calliope (Accessed: 16 June 2023).
