*3.2.1 Ideal headphone monitoring system*

We identified 50 phrasings from the respondents' free-format verbal descriptions of their ideal headphone monitoring system. These phrasings were classified into three major categories, namely Sound Quality (n = 24), System Technical Quality (10), and Physical Properties (10); and into three minor categories, namely Click (3), Ambiance in the Studio (2), and Forgetting the Headphones (1). The most-reported concepts for each major category were Realism (8), Instrument balance (8), and Control over monitoring (6). **Figure 1** displays the classification into emerging concepts and categories of the 31 phrasings coming from improvisers and the 19 phrasings coming from conductors separately, since a Yates' chi-squared test revealed a significant difference between the answers' distribution into the six categories for conductors and improvisers (χ<sup>2</sup> (5,50) = 2,97, *p* < 0.05).
