The link that exists between sound and visual perception in musical creation environments has been one of the most recurring and natural arguments in terms of understanding, analysis and aesthetic appreciation of a musical work. From the beginning of the most remote sound production is the human factor and thus, the gestural expression that from this comes off. Since the appearance of the first devices that enabled the development of the music produced by mechanical means, the human component went from being a prima donna to a mere backstage sceneshifter. In the specific case of electroacoustic music that is not associated with human interpretive component through acoustic instruments or associated visual interventions, the listener is in a new stage of cognitive perception. Parameters of space, cognitive and sensory manipulation and interpretive gestures through interaction and recording devices such as sensors, establishing a new framework in the approach to musical expression. In any case, given the multidisciplinary approach that is associated with art that has to do with sound in the last century, there still remains sound-image correlations that creates a renewed semantic with regard to the musical heritage and performance with nineteenth acoustic instruments that still make up the majority of orchestral templates.
In this doctoral thesis, entitled 'Electoacoustic: the expression of sonic gesture' there have been explored the new shoots that have emerged over the past 70 years following the onset of the first experiments of Pierre Schaefer in the el Groupe de Recherche de Musique Concrète (GRMC) in French radio and the founding of the Electronic Music Studio of Radio Cologne in the 50s where Karlheinz Stockhausen explored the possibilities of sonic expression from electronic production systems. The research has been structured in six chapters: in part 0 the theoretical context is presented, which will identify the roads that will run the investigation and in which the concepts and approaches that will serve as a foundation in the following five chapters will be delimited. This part provides an overview on the definition and terminology of this language as well as a review of the major discoveries and advances that have led to the current stage of electroacoustic music. The following five chapters (essays 1 to 5) make up the practice part. Each of them addresses a specific and focused approach that allows to investigate and draw conclusions on the different profiles that raises the title of this thesis.
Essay 1 entiteled Contrapunto Acusmático en Vivo deals with the design and composition of a work for recorded media (tape) of open-type, in which the flexibility and adaptability of the fixed media and the analysis of sound production unconnected parameters are questioned. In this case, a person reads a poem associated with a specific theme (Peranakan culture in Singapore); an application programmed in Max MSP analyzes some parameters that have to do with that user's voice; at the end of the reading, the result of the work can be heard. Thus, the final characteristics of the work are conditioned by the parameters extracted from the analysis of the voice of the reader. The following essay, TanGram, investigates the interpretive stage of electro-acoustic percussion quartet; in this it is developed a work for 4 tam tams and 4 Nintendo Wii remote controls that the 4 players have fastened to their arms, allowing exploring the gestures and expressive possibilities in a musical performance for instrumental ensemble with live electronics. In the third essay, Augmented Sound, a visual installation that reacts to the sound and movement of jazz interpreters is proposed; in this case an Augmented Reality scenario is created to visualize the sound of these performers from a Jam session, preceded through a phase of learning by means of a workshop. In essay 4, Electroacoustic and video-performanza, it is investigated the electroacoustic music creation for a video-dance with an approach and a specific profile such as site-specific. In the last essay, Spectromorphology and visual gesture, the consistency and coherence between sound and image from the postulates of the electroacoustic language spectromorphology are investigated; the results of this part will lead to the composition of the sound part of a video documentary entitled ‘Manos que dan forma’. 
Finally, and apart from the conclusions drawn directly from each essay, some conclusions are presented in which not only criteria from each of the covered topics are stablished, but also the different parts are compared in order to critically evaluate the obtained results, both the adequacy of the devices used and the reached success in the artistic and/or conceptual levels.