Editing Mechanical synthesis (section)

== Key Innovations. Impact ==
The era of mechanical 'talking machines' in general, and Kratzenstein's approach in particular, laid the fundamental groundwork for the development and practical applications of phonetic theory. These approaches were instrumental in advancing our understanding of the fundamental principle that resonances created by specific configurations of air cavities accentuate the spectral components of a sound source<ref name=":3" />. Even in these early attempts at mechanical speech synthesis, it became evident that a complex interplay of elements, including flow of air (like the one from the lungs), vibratory sound source (such as the larynx), and sound shaping through a tube, was necessary to achieve speech-like sound. These insights influenced the further developments of phonetic theory primarily by proving that the intuitions that had existed so far were valuable, correct, and practically reproducable.

Furthermore, the source-filter theory of speech production, explicitly articulated and introduced in the 1960s, built upon principles that had been implicitly recognized in Kratzenstein's and [[Wolfgang von Kempelen's Speaking Machine (1769)|von Kempelen's]] endeavours of mechanical speech synthesis. The need for a source of sound, as well as the acoustic shaping of sound through a tube were present even in these initial attempts, a historical continuity which underscores the relevance of early mechanical efforts in shaping our theoretical understanding of speech production.

Last, but not least, one of the enduring challenges in phonetics, the many-to-one relationship between vocal tract geometry and acoustics, originated in the early experiments such the one of Christian Kratzenstein, and is still -- though maybe not to the same extent -- a topic of debate in the field. Overall, these early mechanical attempts, often perceived at that time as merely a source of amusement and enetertainment, encapsulate the early views on theories of speech production, as some of the challenges encountered continue to be a subject of contemporary research, demonstrating the lasting impact and relevance of the insights gained from these early mechanical speech synthesis endeavours<ref name=":1" />.