The link between the perception of subjective loudness and the total sound level, G, and, more generally, the ambient sound power level at the listener's ears, has been established for some time. However, new results from laboratory experiments as well as real-hall listening tests indicate that the link is slightly more complicated. These studies suggest that the auditory system monitors the strength of the early part of the room response (corresponding to a perceptual factor of ``presence``) and the late part of the room response (corresponding to a perceptual factor of ``room effect'') separately. Evaluation of subjective loudness occurs only at a higher level of the auditory system. The results corroborate other investigations in showing that listeners can evaluate different contributions of the room in separate streams of attention.