## 5 Conclusions  
This paper presented a study into the perception of perceived spatial impression in a concert hall, at different listening positions and for different head orientations. Two complementary experiments were conducted for the elicitation of perceptual attributes: an in-situ experiment which maintained the ecological validity of the actual space and a laboratory experiment which facilitated the elicitation process and addressed some limitations observed in the in-situ experiment. The repertory grid technique (RGT) was used as the elicitation methodology for its robustness and structured approach towards stimuli comparison. An additional audibility test was carried out during the laboratory experiment which facilitated the filtering of salient perceived spatial impression attributes. Verbal protocol analysis was used for the classification of the elicited attributes based on their semantic meaning. Cluster analysis was used for grouping the elicited attributes based on the ratings received in the construct rating stage of RGT, thus facilitating the observation of different perceptual effects. Results showed a good agreement between the in-situ and laboratory experiments. In terms of listening positions and head orientations, the resulting clusters matched exactly between two tests. Ten salient attributes were presented, and future experiments were proposed for in-depth research into the interaction between the attributes and the different listening positions and head orientations. It is believed that the Perceived Source Loudness (PSL) and the Apparent Source Distance (ASD) can affect the more established Apparent Source Width (ASW) attribute. It was also theorised that the Listener Envelopment (LEV) is comprised of two perceptual sub-components: Perceived Reverb Level (PRL) and the Apparent Reverb Width (ARW). It is also believed that the Perceived Reverb Level may be affected by the directionality of the echoes and reverberation. The findings of this study have various useful practical implications, for example on the dynamic rendering of auditory spatial impression in the context of 6 DOF XR applications, where the user can virtually navigate through a space or is teleported to various positions. One other application might be in real concert halls, for the prediction of different attributes' (e.g., LEV) variation depending on different seating positions. Future experiments testing these hypotheses will be carried out for a more in-depth understanding of how different spatial impression attributes are perceived in the context of multiple positions and head orientations. Subjective grading tests will be carried out in a controlled environment and will assess the salient spatial impression attributes in a multi-position and multi-head-orientation context.  
Conceptualisation, B.I.B. and H.L.; methodology, B.I.B. and H.L.; software, B.I.B.; validation, H.L.; formal analysis, B.I.B.; investigation, B.I.B. and H.L.; resources, B.I.B. and H.L.; data curation, B.I.B. and H.L.; writing--original draft preparation, B.I.B.; writing--review and editing, H.L.; visualisation, B.I.B.; supervision, H.L.; project administration, H.L.; funding acquisition, H.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the University of Huddersfield, grant number URF510-01.  
**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.  
**Data Availability Statement:** The room impulse responses used for the laboratory experiment in this study are available from [[https://doi.org/10.5281/zenodo.2641165](https://doi.org/10.5281/zenodo.2641165)]([https://doi.org/10.5281/zenodo.2641165](https://doi.org/10.5281/zenodo.2641165)).  
**Acknowledgments:** The authors would like to thank everyone who participated in the listening tests.  
**Conflicts of Interest:** The authors declare no conflict of interest.
Figure 11: Elicited terms along with the RGT ratings from the laboratory test.