The first is the purest chord there is, rising up from a core E-flat in the bass. It's Pythagoras' chord of nature, the lowest tones of the harmonic series sounding together. The C minor is the relative minor of E-flat: two of the tones, E-flat and G, are the same in both chords. It's the natural harmony tilted downward, turned toward the darkness. Finally, E-flat again, but it sounds more sober and resigned, as if the darkness of C minor has been subsumed into the light. It is "first inversion," meaning that there is a G instead of an E-flat in the bass. The bass notes — E-flat, C, G — together spell out C minor, again bringing out the shadows of the scene. Yet the top notes — E-flat, G, B-flat — anchor the sequence melodically on the major triad.
This combination of technical savvy and elegant expression is why my students have all preferred Alex's New Yorker reviews to those of Midgette, Tommasini, Gann, Kindelsperger, et al. (Nick Kindelsperger writes music reviews for the student newspaper here.) Yes, the Magic Flute is an opera, so ACD might excuse such language as it can be used to illuminate the drama. Except, Alex does not link this description to any of the dramatic themes of the opera, treating the overture as a separate and absolute piece of music. This overture, and any interpretations of it, gets re-evaluated once the action starts. The drama affects and is affected by the aesthetic environment set in the overture. But this is just as true of the introduction to a Beethoven symphony or a Schubert sonata. As contexts change and expand, our perceptions of events change. The recently departed guru of Harvard's Music Department, David Lewin, devised an equation to express this sentiment:
p = (EV, CXT, P-R-LIST, ST-LIST)
EV is the observed event and CXT is the context in which the event is observed. P-R-LIST is a list of perceptions and the relationships p has with with these perceptions, and ST-LIST is a list of statements interpreting the relationships. These arguments combine to produce the phenomenological p, the perception itself. Alex describes part of p for the opening chords of the Magic Flute given the very brief context (CXT) of only those first chords. As the opera progresses, CXT expands so p of those first chords will naturally change. The P-R-LIST and ST-LIST will likely become larger, though some items on that list may be deleted by further information. Speculations can be proved false, deadends that are no longer viable perceptions.
It is the use of "technical language" -- terms describing the music itself -- to make the list of relationships and to interpret these relationships that I find so crucial in the communication about music. This is why I study music theory, and why I teach music theory.