2.1 STETHOSCOPIC FORMS OF LISTENING
A certain use of piezo can be defined as stethoscopic when the movements performed with the contact microphone on the body of the instrument, recall the ones of the stethoscope on the human body...
In the previous chapter, I have considered diverse artistic experiences in a quite narrow time window, from the '60s to the '80s. From then on, the use of contact microphones has become common in a huge and diverse range of artistic experiences, most of them related to sound art and experimental music. The low cost of piezoelectric elements and their robustness are the main practical reasons for the spread of piezoelectric disks, whose technological features have been curiously kept as they were in the '80s, while at the same time, different applications of piezoelectricity underwent a remarkable development. There is a sort of gap between the technological and scientific progress of piezoelectric devices, and the use of piezoelectric elements for the construction of contact microphones or hydrophones, in the realm of experimental music and sound art. Enormous progress has been made in the direction of micro-size: nowadays piezoelectric devices tend to be built-in electromechanical microsystems, covering a wide range of different applications from automatization to bioengineering and biomedicine. Hence, it is no longer possible to manipulate or hack advanced piezoelectric devices. While piezoelectric elements used to build piezoelectric contact microphones have maintained a hand-size/finger-size, crucial to manipulation. The lack of correspondence between the scientific progress of piezoelectric technology and its adoption in experimental music experiences can be ascribed to the miniaturization of piezo technology and the subsequent loss of physicality and impossibility of a hands-on approach. If some technological upgrades are evident in the comparison between the first experimental experiences and the work of contemporary artists, they consist, above all, in the inclusion of software, controllers, video, and any other kind of implementation of the electronic system. But the technology of piezoelectric disk is basically kept as it was, pointing to the importance of manipulation, and DIY ethic and method.
In the context of contemporary experiences with piezoelectric microphones, my project Composing with piezo confirms the use of the old-school technology of piezoelectric microphones (simply piezos, from now on). One peculiarity of this project relies on the fact that self-built microphones are used with acoustic instruments, combining rough DIY tools with finely designed and highly perfected traditional instruments. Moreover, piezoelectric microphones are here used both to amplify instrumental sound and to produce otherwise unheard sounds, through a reinterpretation of a few instrumental techniques, such as glissando, tapping, scraping, etc, by playing the instrument directly with the contact microphone. Usually a contact microphone such a piezo is simply placed on the soundboard of an instrument to amplify it, capturing the vibrations of its surface, that are transduced and converted into the electric signal. When, instead, the piezo is used to play the instrument (moving it on its strings, on its surface, etc) its role changes: the piezo provokes sounds while detecting them through the contact with the resonant surface. This stethoscopic use of the piezo calls into question several issues, concerning the usual perception of sound in the listening experience, the instrumental use of microphones, also in relation to the contemporary tendency of extending the usual techniques of instrumental playing, and lastly the role of piezo within the compositional process.
2.2 INSTRUMENTALITY OF PIEZO: SHOULD PIEZO BE INTENDED AS A MUSICAL INSTRUMENT?
A stethoscopic use of the microphones foresees its delivery into the hands of the musicians. In my project, as well as in the examples already seen of Cartridge Music by Cage...
2.3 ALTERATION OF THE INSTRUMENTAL SYSTEM
I should start by considering the dynamic nature of the system consisting of the performer and all the components of the musical instrument...