It's almost difficult to add to the praise that has been heaped on these recordings. Somehow Bernard Haitink works a very special magic with these scores, and the Royal Concertgebouw Orchestra is equally incandescent. Somehow Haitink's relatively laid-back approach really suits Debussy's ebb and flow. As just one example, the climaxes in "Nocturnes" seem to occur naturally, fairly leaping out of the haze, but then the composer lures you back into his shadowy, quiet world -- Haitink captures all this beautifully.
Some say the orchestra was in its glory days under Haitink. I don't quite agree, having heard them do marvelous work under Chailly and others, but in any case, they were playing at their absolute finest here. The shimmering effects actually *sound* that way, and if you've ever heard an orchestra play Debussy badly, you'll know what I mean. The ensemble's renowned woodwind section sounds glorious, and Debussy gives them many, many opportunities to show off.
Dating from the 1970's, these recordings are excellent, and you might not even think about this issue because the sound quality is so superb. Occasionally a very marginal amount of tape hiss can be discerned -- but now we are truly splitting hairs, since these pieces were recorded in the late days of the analogue era.
Like Haitink's Bartok set with the same orchestra (also two discs), this is fairly essential for those who love the composer. And with its reasonable price, this is not only an essential Debussy recording but a bargain as well.