Since its conception, Denis Smalley's spectromorphology has equipped listeners and practitioners of electroacoustic music with appropriate and relevant vocabulary to describe the sound-shapes, sensations and evocations associated with experiences of acousmatic sound. This liberation has facilitated and permitted much-needed discussion about sound events, structures and other significant sonic detail. More than 20 years on, it is safe to assume that within the electroacoustic music community there is an agreed and collective understanding of spectromorphological vocabulary and its descriptive application. Spectromorphology's influence has been far reaching, inciting approaches to electroacoustic music analysis (Thoresen 2007), notation (Patton 2007), composition and education through its flexible functionality and accessible pool of vocabulary.

The concepts introduced by Smalley in the context of space-form (2007) have firmly put acousmatic music on a discourse of spatial exploration, holding much potential for the developing of aesthetics in new directions. This article approaches space from the low level of musical structure, with a multi-dimensional attitude to space-form, exploring spatial texture, a concept introduced by Smalley to describe the temporal formations of space in spectromorphology (1997). Spatial articulation is investigated in the context of granular-oriented textures, proposing a micro-spatial, perceptual morphology – the texton – as an aesthetic approach to acousmatic music. This follows Albert Bregman's speculation regarding equivalents to visual perception in texture, where the theory of textons was first developed by the neuroscientist Béla Julesz.

The article discusses acousmatic textons, in terms of intrinsic properties, the way they propagate in time, and how they organise in distributions to form spatial textures. The emergent macroscopic qualities of textonal formations are also reflected upon in the introduction of a group of textural states, where source-bonded spaces and abstract musical thinking coalesce.

This four-part exposition revisits Denis Smalley's concept of sound surrogacy from a critical constructive approach. In the first part, Smalley's article from 1997 serves as a point of origin for a close investigation of his concept. We examine the precise definitions and demarcations in his concepts and we attempt to systematise the model. In the second part of the investigation we attempt to solve some of the problems in Smalley's model by suggesting a new surrogacy model originating in Smalley's idea, but with a more formal structure and obvious demarcations. Having presented this new surrogacy model, with references to Georges Bataille's theories on base materialism as well as anthropological studies, we attempt to create a new order of surrogacy that in its object relation is positioned beneath Smalley's first-order surrogacy (as the remote surrogacy order is placed above the third-order surrogacy) – an impossible/paradoxical category that will be termed transgressive sound surrogacy. In the fourth part we demonstrate this new surrogacy order in a series of examples found in art and culture.

Denis Smalley devoted himself to the elaboration of a method based on the analysis of spectral transformations by connoting sonorous motions and adopting metaphors borrowed from non-musical contexts. While considering Smalley's earlier theorising within the context of past and contemporary research, this paper focuses on the use of non-musical models in spectromorphological design in order to show how sonorous qualities, imaginative factors and extra-musical meanings concurred in defining new cognitive itineraries and in extending the terminology adopted, thereby establishing the basis of a new compositional approach.

By drawing concept diagrams of Smalley's seminal writings, I have attempted to show how Smalley's ideas on acousmatic music have evolved from manipulating sound objects to creating ‘space-forms’. The work Wind Chimes is analysed with respect to spectromorphology and sound shapes, and it is compared to the work Base Metals, which is analysed with respect to spectral space. A connection is then made between the evolution in writing and the evolution in composition.

This paper examines the use of soundscape elements and mimetic sound-identities in the music of Denis Smalley. It attempts to reconcile these elements with the acousmatic tradition from which his music emerges, illustrating that it does not represent a contradiction, but rather a refined aesthetic where spectromorphological and soundscape concerns relate in symbiosis. A close look at key works, including Empty Vessels (1997), Valley Flow (1992) and Pentes (1974), reveals how these elements manifest themselves in his work, and how the spectromorphological and soundscape aspects of these pieces work together toward shared goals.

Inspired by Denis Smalley's theoretical ideas on spectromorphology and Albert Bregman's (1990) auditory scene analysis, I began an investigation into the formation and segregation of timescales1 in electroacoustic music. This research inevitably led me to an exploration of the factors that shape our perception of time passing and estimation of durations, where spectromorphological issues intermingle with extra-musical associations, autobiographical experiences, emotional responses, and the surrounding environment at the time of listening. Ultimately, time perception affects the structural balance of a composition. This paper, which is part of my ongoing research, examines how the perception of time is affected by the semantic meaning and the spectromorphological characteristics of sound events.

ENACTIV is a project that addresses, explores and offers solutions for converting a performer/composer's expressive sonic and kinetic patterns into continuous variables for driving sound synthesis and processing in real-time interactive composition. The investigation is inspired by the achievements in cognitive science, in particular Umberto Maturana and Francisco Varela's Santiago Theory (1980, 1987), in which the authors explain how the process of cognition arises through ‘structural coupling’ – a mutual influence among living beings, and living beings (humans in particular) and the environment, and how this process stipulates certain patterns of organisation driving the individual's behaviour.

The project investigates how a composer/performer's cognitive archetypes, which have been developed via his or her ‘structural coupling’ with the social and natural environment and expressed through voice and unwitting hand gestures, can be associated with or ‘mapped’ onto sound synthesis and processing parameters in such a way that the system will play an active role and act reciprocally, involving a certain degree of variation and unpredictability at its output. The aim of the project is to develop a creative tool which will allow professional musicians, multi-media artists and non-expert participants to engage with multi-modal improvisation in an intuitive way.