I don't know why in general, successful reproduction at low levels, is'nt a clear priority in assessing a system. Reviewers talk of neutrality, dynamics etc, but never low volumes. To many people, it is a real priority, we have families and neighbours to consider. I happen to agree about about tubes and relatively efficient speakers with flat impedence. Big SS amps and low efficiency multi driver speakers, seem to get going at higher volumes. I think though that most systems will shrink the soundstage at low volumes and lose some dynamics.