When an opera company moves into a new home, there’s always lingering nostalgia for the old one. But fans of the Metropolitan Opera were more than ready to vacate the worn old Met at 39th Street and Broadway for a massive new theater at Lincoln Center. The old Met, I vaguely remember from attending a few performances as a teenager, had fine acoustics and, with its golden horseshoe interior, a kind of faded, dusty grandeur. But backstage resources were woefully inadequate.

The new house, which opened on Sept. 16, 1966, with the premiere of Barber’s “Antony and Cleopatra,” excited both the company and its audience. The auditorium and lobbies combined old-world elegance and a smart, contemporary look. With nearly 3,800 seats and some 245 standing-room positions, the auditorium was enormous, yes. But back then bigness was considered an asset, and attendance was typically good. Almost everyone agreed that the acoustics were excellent. (Many still believe the best sound is up in the balcony and family-circle levels.) With its hydraulic elevators and gargantuan space backstage, the theater set a new standard in stage technology. Of Lincoln Center’s constituent organizations, the Met is the only one that has been basically satisfied with its building from the start.

[ Triumph, tragedy and 50,000 hats: the Met Opera by the numbers ]

On Sunday, May 7, the “New Met” will celebrate its 50th anniversary in its home with a gala concert. It’s a good time to ask: Is the house still meeting the company’s needs?

Is the Met just too big?

During the first couple of decades at Lincoln Center, the size of the house served the company’s purposes. Today, though, as the Met struggles to maintain the loyalty of opera lovers while trying to entice newcomers, room for some 4,000 presents a challenge. For the 2015-16 season, sales averaged 2,869 seats per performance, a turnout that would have overflowed, say, the Royal Opera House in London (2,256 seats). But that left a lot of empty seats at the Met.