“Welcome to… whatever this is,” said Don Henley, making his first remarks to the full house gathered for the first night of the Eagles’ residency at Las Vegas’ Sphere Friday night. For however much preparation had assuredly gone into putting up a 20-night engagement in the massive dome, Henley sounded in those five words just as nonplussed as any veteran of the low-glitz 1970s probably ought to be. “We’re just the house band,” he added, offering some vaguely neutral comments about “21st century entertainment” and quipping, “I hope you brought some Dramamine.”
Not that Henley really meant to bite the hand that is feeding him. (Nor would he, likely — the Eagles’ manager, Irving Azoff, is as deeply involved in Sphere as anyone.) And there was no doubt Henley was speaking in approving terms when he made a few comments about the sound, noting that there…