The Dutch language is closely related to Low German, but for at least the past two centuries the Netherlands' cultural relations have been as close with France as with any other country. (Vincent van Gogh, after all, went to France to paint.) So it's quite appropriate that the first of the Royal Concertgebouw Orchestra's programs at Davies Symphony Hall, performed on Sunday, should consist of French music. And as the Concertgebouw Orchestra is the greatest and most renowned of Dutch ensembles, it chose to play what are perhaps the two greatest and most renowned of French symphonies. True, Claude Debussy labeled his La Mer, on its publication in 1905, merely as "Three Symphonic Sketches." He was being modest. This is a work on the scale of a full-size symphony, and with the weight, complexity, and integration of one. Had the composer chosen to apply the label, no one would have thought it inappropriate. But although La Mer is heavier and far brasher than is typical of Debussy's earlier work, it is still an essay in timbre and washes of sound. Under Principal Conductor Mariss Jansons, the Concertgebouw Orchestra brought a bright, clear sound, appropriate for the resonant acoustics of its home auditorium, for which the orchestra is named. It was almost too harsh for Davies, yet with an orchestra of this skill it was rich and blended. Any listeners who'd been out to the shore in the previous few stormy days would recognize Debussy's depiction of the sea. Waves of sound suddenly rose up and crashed throughout the work. Winds and strings exchanged phrases with precision but unpredictable passion. The first movement's grand coda arrived almost out of the blue, instead of grandly following from the preceding chorale. Under Jansons' careful and expressive conducting, though, all was balanced and well-judged as part of the whole. Debussy felt slightly embarrassed about his great predecessor Hector Berlioz' Symphonie fantastique. He thought it a feverish and extravagant work. Berlioz painted in great swaths of bright primary colors, whereas Debussy would carefully tint with subtler shades. Yet Debussy might have found something familiar and comprehensible about the Concertgebouw's performance of the Fantastique. The opening of the first movement of "Reveries and Passions" was full of hesitant pauses and sudden onrushes, like a return to Debussy's ocean. This approach set the tone for the work. Little touches, like a slight swell in volume in the brass notes at the end of the "March to the Scaffold" (echoing the rumble in the timpani representing the distant storm at the end of the previous movement, "Scene in the Country"), were reminiscent of that slight sense of unpredictability hiding in La Mer.