This paper discusses the influence of acoustics on temporal aspects of performance for different instrument constellations. In a concert hall with mechanically variable acoustics, professional soloists and ensembles each performed a programme of 3– 4 pieces at three trials throughout the same day in the presence of a small audience of experienced musicians-researchers, most of whom also participated in the project as performers. The instrument settings included solo instruments, chamber ensembles and a chamber choir, with a repertoire ranging from the 17th  to the 21st century. The trials were recorded for later analysis. The microphones were placed so as to minimize audible differences in acoustics between the recordings.

For the solo instruments musicians tended to use slower tempi and to allow themselves more agogic freedom in larger acoustics. A somewhat similar tendency was observed in conducted ensembles. For ensembles without conductor, the influence of acoustics on the chosen tempi was less marked.

In larger acoustics, performers tended to feel more at ease, which was often reflected in slower tempi as well as in more tempo fluctuation. The listeners in the hall, on the other hand, did not always share the performers’ preferences. A different picture emerged in the evaluations of the recordings: here musicians viewed recordings made in drier acoustics, often using faster tempi with less fluctuation, in a more positive light. For some pieces in slow tempi, however, performances in larger acoustics were preferred. Generally, the preferences of musicians and listeners were more in agreement for the recordings than for the live performances.

The results show that acoustics in many cases does seem to influence tempo and agogics, but also that this influence varies considerably between different instrument settings (especially solo vs. ensemble) as well as between individual pieces in different tempi and styles. The difference in performers’ preferences between live situations and listening to recordings raises the question of what is to be regarded as ‘good’ acoustics: that which is spontaneously experienced as such by the performer, or that which stimulates performances that are judged as ‘good’ when listened to by the performers themselves?

The experimental performance sessions described above took place in the new concert hall Studio Acusticum, Piteå, Sweden, which, with its variable acoustics (enabled through lowering and raising the ceiling), was designed to serve simultaneously as a public ‘stage’ and as a laboratory for artistic research in music. The variable acoustics is a precondition for this project, in which research activities not only relate to but are inseparable from artistic production, in this case performative interpretations. The results highlight the different experiences of performers in onstage and audience situations, as well as of performers and audience live in the hall and when listening to recordings, and they suggest that artistic criteria do change in the context of experimental artistic research. The project involves, besides musicians, researchers in audio engineering, and its results are relevant for the future design and use of concert halls, as well as the design of recording sessions.