Digital Musical Instruments (DMIs) offer new opportunities for collaboration, such as exchanging sounds or sharing controls between musicians. However, in the context of spontaneous and heterogeneous orchestras, such as jam sessions, collective music-making may become challenging due to the diversity and complexity of the DMIs and the musicians\u2019 unfamiliarity with the others\u2019 instruments. In particular, the potential lack of visibility into each musician\u2019s respective contribution to the sound they hear, i.e. who is playing what, might impede their capacity to play together. In this paper, we propose to augment each instrument in a digital orchestra with visual feedback extracted in real-time from the instrument\u2019s activity, in order to increase this awareness. We present the results of a user study in which we investigate the influence of visualisation level and situational visibility during short improvisations by groups of three musicians. Our results suggest that internal visualisations of all instruments displayed close to each musician\u2019s instrument provide the best awareness.<\/p>\n