I have two massive resonances (more than 12db above the response curve elsewhere) with my bookshelf monitors placed on a desk in a large furnished, carpeted room. One is at about 110 Hz and another at about 250 Hz.
Are there any rules of thumb for determining whether response issues stem from the speakers themselves or from the room and/or placement besides common-sense "move the speakers to another location and re-measure?" Specifically, I'm looking for reasonable numbers I can expect for typical furnished rooms/placement effects.