The passion of Prof. Lokki is to understand how rooms modify sound that we hear. To pursue the encompassing understanding of room acoustics, his research team is investigating auralization, spatial sound reproduction, binaural technology, and novel objective and subjective evaluation methods, as well as physically-based room acoustics modeling methods. Particularly, the interest has been in concert halls, in which the team has developed new measurement techniques, analysis methods for spatial impulse responses, and sensory evaluation methods to understand the perceptual differences between concert halls. Furthermore, Prof. Lokki has been continuing a long-term research on augmented reality audio, eyes-free user interfaces, and recently novel hearing protection devices and research on hearing in noisy and reverberant conditions.