Previous research has considered theoretical perspectives on the design of musical interfaces. Gerzso (1992) stated that in all cases the systems embody a particular approach to making music. Such approaches which arrive with assumptions about the nature of music, musical representa- tion, and interaction. For instance a time-line based interface such as found in applications such as Cubase1considers music in terms of musical events which are arranged in a pre-defined tem- poral order. Magnusson (2006) goes further by using semiotic theory to describe the design of music software in terms of as a process of combining signs and interface metaphors with compo- sitional ideology, to create a system which allows users to express their ideas and communicate
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their ideas, whist at the same time opening up the possibility for new ideas and ways of thinking to emerge. Magnusson (2006) describes three ‘interaction paradigms’ within musical computer interfaces, the ‘computer-as-tool, computer-as-partner, and computer-as-medium’. However, less emphasis is placed within this work on the role of computers in a collaborative context where multiple people are simultaneously creating music together.
As previously discussed in this thesis, there are no clear boundaries between different kinds of musical activities, musicians approach musical creativity in different ways, and the activity of making music has no clearly defined end point or criteria for evaluation. Furthermore, it is essential to realise that the tools, instruments and interfaces employed in the process of making music influence the musical outcomes that are realised, and also affect the ways in which multiple people interact during the process. Musicians also have a tendency to re-appropriate technologies for new purposes (Cascone, 2000), making it difficult to predict how features within an interface will be used, and making it difficult to reason about how people will interact with each other. These properties of musical interaction make it difficult to formulate a design specification for a musical interface, and designers are consequentially placed in a position where they too must explore and experiment to arrive at interesting solutions. Put another way, Cook (2001) stated that musical interface construction perhaps necessarily ‘proceeds as more art than science’.
Much like the activity of music-making itself, the challenges of designing technology to sup- port musical interaction feature many of the traits of a ‘wicked problem’ (Fitzpatrick et al., 1998, Ritchey, 2005). The following points, adapted from Ritchey (2005), demonstrate the aspects of designing for CDMI which can be regarded as ‘wicked’:
• the open-ended and ambiguous nature of musical interaction makes it difficult to formulate an exact specification for the software
• There is no stopping rule in the development process, features can be added or extended indefinitely
• Judgements about the software (i.e., evaluations) indicate ‘better or worse’, rather than true-or-false
• There is no immediate and no ultimate test of a solution • There is an infinite set of potential solutions
3.5 Summary
This chapter has outlined Collaborative Digital Musical Interaction (CDMI). Whist acknowledg- ing and building upon previous descriptions of Digital Musical Interactions, CDMI focuses on the interaction surrounding group music-making which is mediated by technology. Particular facets of CDMI which have been explored in this chapter include the ways in which sound as a medium distinguishes musical collaboration from other forms of collaboration, and the ways in which technology makes CDMI different from other forms of musical interaction. This chapter has also broken down CDMI in terms of the communication constraints defined by Clark and Brennan (1991), so as to understand the role technology can play in altering the ways in which musical interaction can proceed. The following chapter briefly discusses the research methods adopted within this thesis, and introduces the collaborative music software developed in order to carry out the empirical studies.
Chapter 4
Methodology
The first section of this chapter discusses the motivations for employing lab-based user studies. The second section (Section 4.2) justifies the reasons for developing a piece of bespoke software for use within these studies, and presents some general details about the implementation of this software. This chapter serves as a general introduction to these issues; more specific details of the methods and software environments used in the studies are given in their associated chapters (Chapters 5, 6, 7).
4.1 Methodological Approach
The literature review identified several approaches to studying group work and collaborative in- teraction. Broadly speaking, the two approaches most commonly seen in CSCW research are naturalistic observational studies of people engaging in work activities, and lab based experi- ments. Observational studies typically use ethnographic techniques (Heath et al., 1995, 2002b), or frameworks such as Distributed Cognition (Furniss and Blandford, 2006, Hutchins, 1996). This approach has been used in the study of groups of musicians writing and rehearsing in re- hearsal rooms (Nabavian, 2009), and also ensembles of electro-acoustic musicians collaborating in real-time (Merritt et al., 2010). However, this methodological approach requires access to a group of subjects who can be observed whilst engaging in their collaborative activities over a sustained period of time.
Although it has been suggested that the evaluation of collaborative musical interfaces should occur in a setting which is as close as possible to a ‘real context’ (Xamb´o et al., 2011a), a number of issues discouraged the use of purely observational methods within this thesis. Firstly, the forms of shared interface designs this thesis set out to investigate are not commonly used by groups of collaborating musicians, making it difficult to find suitable groups of experienced users to observe. This also makes it difficult to identify an existing ‘context’ within which to perform an evaluation. Secondly, should such a group of musicians be located, gaining sustained access to them for the purpose of conducting the observations may not be easy. Thirdly, a purely observational approach, by definition, does not allow for the use of experimental manipulations or interventions, meaning it would be difficult to perform explicit comparisons between different interface designs. The scarcity of established groups of users to observe also excludes the user of more design orientated methodologies such as participatory design.
For these reasons, the studies presented in this thesis use a controlled experimental approach, whereby groups of musicians are observed in a laboratory context, and presented with a number of different interface variations. The decision to use short controlled studies was also positively motivated by several factors which mitigate against the unnatural context of experimental studies. In particular, such an approach bypasses the need to locate existing groups of musicians, and makes it possible to introduce experimental interventions such as changing features within the interface. Lab based studies also provide a greater degree of control over the study context and the data collection process. For instance they provide the opportunity for detailed logging of user interaction which would not be possible through an observation of people using software which was either commercially available or constructed by the musicians themselves. Secondly, the controlled nature of the studies enables statistical comparisons to be made between groups of participants exposed to different experimental conditions.
The use of short controlled studies also makes sense given the infancy of research within the field of collaborative music. The limited knowledge currently available about how people use shared interfaces for music-making means that there is still a lot to be learnt from small controlled studies, as demonstrated by the contributions of this thesis. In particular, rather than focusing on a limited number of people, the use of controlled studies allowed for a large number of participant groups to be observed, and enabled a range of different interface designs and features to be compared. As systems for CDMI become more widely adopted, the use of purely observational
naturalistic studies will surely become more beneficial. This is acknowledged as future work. Finally, the lack of commercially available collaborative music software for real-time interac- tion required the development of a new piece of software as a vehicle for conducting the research, although the timescale of this PhD restricted the amount of time that could be spent developing software for the purpose of running experiments. The construction and testing of software is an involved process, and designing and developing a compact prototype interface which is suitable for conducting short user studies is considerably less complex than creating a large, fully fea- tured application which would be suitable for use in multiple sessions by experienced users over a long period of time. Given the paucity of information about the design of collaborative musical software, developing a large-scale application would arguably have been a premature step for this research. Without identifying and understanding some of the primary issues for a CDMI system, the development of an application for use in a large scale observational study would largely have been based on guesswork. The contributions this thesis makes can in this sense be regarded as an incremental step towards the design of a more featured application which could be used in a large scale study. An overview of the software developed for this thesis is described in Section 4.2, whilst the details of the interfaces used in each study are presented in their respective chapters.
4.1.1 Study Methodology
During experiment sessions groups of musicians make music using a collaborative music envi- ronment. The groups are presented with different software interface designs. Observations are taken to understand how this impacts on the way the groups of individuals use the software, their approach to organising collaborative activities and their reported preferences. This approach is inspired by CSCW studies such as that by Gutwin and Greenberg (1999), where various interface features are presented to assess the usability of groupware software. Quantitatively measurable features within interaction using automatically collected interaction log data from the software and multiple choice questionnaires. Video observation and group discussions were also used to gather qualitative data. This methodology is informed by the approach taken in some forms of CSCW research, although the additional qualitative measures extend the traditional CSCW approach to account for some of the distinct properties of CDMI.
This research focuses on studying aspects of group interaction surrounding CDMI, rather than attempting to address issues such as expressivity, which are highly subjective and difficult to operationalise. Similarly, the analysis performed for this research did not attempt to rate, judge
or review the quality or musicality of the music created by any of the study participant groups. Such analysis would involve subjective judgements about the quality of the music, and this was seen as peripheral to understanding how the interfaces presented to participants supported or interfered with music-making processes, and how they influenced the participants’ experiences whilst using them. Furthermore, the interfaces presented to participants featured various forms of incongruence in the way audio was presented, and in the forms of access the interface provided users with (e.g., relating to privacy and sharing of contributions). This incongruence makes it difficult to delimit what might be regarded as the final music the participants created during the experimental sessions, further complicating any hypothetical processes of critique by external judges.
4.1.2 Participants and Participant Groups
A decision was made to study triadic groups of participants (groups of three) in all studies. Inter- action in triadic groups has been identified as distinct from interaction in dyads (two people). For example as part of conversation, gaze has limited value in a triadic group as it is only possible to look at one person at once (Battersby and Healey, 2008). Considering musical collaboration, issues such as ownership become more uncertain and ambiguous in triadic groups, as it less obvious who contributed which sounds, or who performed which actions. In a dyad, such infor- mation would be implicit for both group members. Studying triads also represents a compromise between the logistic challenge of recruiting anticipants and forming groups of more than two people.
E-mail mailing lists were the primary means by which participants were recruited. All three studies sought to recruit people who identified themselves as musicians, people with an inter- est in music technology or people with prior experience using computer music software. As discussed previously, the design of collaborative systems for novice users has been a concern for a number of researchers (Weinberg, 2003), however this places considerably different de- mands on the system design. The decision to use music terminology and interface metaphors similar to those found in conventional music software sets this research apart from collaborative music research aimed at supporting audiences, non-musicians, novice users, children or educa- tion (Bryan-Kinns, 2004, Freeman, 2008, Truman, 2011a, Weinberg et al., 2002). The value of conducting user studies of musical interfaces using novice users has not been fully assessed in previous research, although there is evidence that musicians and non-musicians perceive music
in different ways (Koelsch et al., 1999), and the decision to recruit participants with at least a basic knowledge of music and music technology is also supported by James and Stanton (2011), who demonstrate a language barrier caused by lack of musical domain knowledge in novice users While many researchers have identified social and musical rapport as an important aspect of group musical interaction (Sawyer, 2003, Small, 1998) several factors motivated us to study groups of people who have not previously worked together. Firstly, established groups will ar- rive with a history of shared experiences to draw upon, a shared musical repertoire and estab- lished working strategies. These working strategies and means of communication may be obtuse and difficult to interpret or study. Secondly, studying musicians who have previously worked together may introduce bias between groups, as not all groups will have an equal level of experi- ence. Thirdly, the group’s musical repertoire, group musical knowledge and established working strategies may be stronger than or resilient to the effects brought about by the experimental con- ditions under investigation. Studying groups of individuals who are not familiar with each other introduces control over differences in the level of group experience, as all participants will have an equal level of familiarity with one another. Although it is important to acknowledge that participants will need to build a social and musical rapport and although it is less common for musicians to play with people they have not previously worked with, this is not an entirely un- natural situation. Finally, recruiting groups of strangers simplifies the process of recruitment and allows us to use a larger sample of participants.