Co-design of a Smart Cajón

Abstract

Smart Instruments are a novel family of musical instruments that embed sensors, actuators, wireless connectivity, and semantic audio technologies. This paper reports the findings of a participatory design approach to develop a Smart Cajón, a box-shaped percussion instrument with Internet of Musical Things components. Five initial co-design sessions were conducted with different professional cajón player participants. The players were invited to devise tangible mock-ups by placing provided sensors on an acoustic cajón, and to express desirable use cases and interactions. We then designed and implemented a prototype satisfying performers' common requirements. The prototype was assessed using the concurrent think-aloud protocol. On overall, the smart qualities of the prototype and their potential received positive feedback, and areas of improvements related to expressive control and personalization were highlighted.

Real-Time Hit Classification in a Smart Cajón

“…Therefore, the rendering of the simulated percussive instrument sounds cannot be informed by a plethora of data describing how and where the hit was performed. Consequently, as stated by some of the cajón players we worked with in a previous study (Turchet et al, 2018), the quality of the gesture-to-electronic sound interaction is largely impoverished compared to the level of control intimacy of the acoustic cajón. Enabling subtle interaction and nuances in electronically-controlled cajones is deemed crucial by players (Turchet et al, 2018) and is the focus of the current study.…”

“…The design process was informed not only by the results of the study reported in Turchet et al (2018), but also by consultations with three professional cajón players who were involved in codesign and testing sessions before the final evaluation.…”

“…In previous work, we established design requirements for a smart cajón, following a user-centred approach (Turchet et al, 2018). Specifically, we conducted individual co-design sessions with five professional cajón players, which resulted in crafting and evaluating a prototype.…”

“…In this paper, we investigate a more robust technique overcoming the limitations of our previous method based on spectral centroid. We focus on the design and development of a system capable of addressing some of the suggestions made by professional players that assessed the smart cajón prototype reported in Turchet et al (2018). Those players highlighted the following areas of improvements related to expressive control: (i) track hits on more areas on the front panel, specifically the two top corners; (ii) track hits on the side panels; (iii) improve the sound quality of the triggered samples to render more adequately the type of gesture used (especially in terms of dynamics and timbral nuances); (iv) automatically transcribe the played patterns into a digital score.…”

Towards a Semantic Architecture for the Internet of Musical Things

“…Another instance of SMIs is the smart cajón reported in [55]. This instrument consists of a conventional acoustic cajón smartified with sensors, Wi-Fi connectivity, motors for vibrotactile feedback, the Bela board for low-latency audio and sensors processing [56], which runs a sound engine composed by a sampler and various audio effects.…”