Then what is the period everyone recalls so fondly, the era that makes the present seem so fragile by comparison? Surely there was a time of true peace and prosperity — perhaps during the salad days of the currently reigning generation of 50- and 60-something administrators and commentators?

“I think there were, like, six years in the 1980s,” Mr. Miller said, half joking. Yet even those six years seem questionable: they apparently didn’t include 1987, when, in the Jan. 19 edition of The New York Times, John Rockwell wrote: “More of America’s symphony orchestras are in trouble than at any time since the Depression — afflicted with strikes and lockouts, struggling to raise money and in some cases canceling seasons and even declaring bankruptcy.”

The golden age, if indeed it existed, must have been fleeting and local, making it more sensible to think about the future than dwell on divergence from a misremembered past. What will the American orchestra be like in 2050?

Once people got over their surprise at being asked that question — orchestras are generally focused on meeting next week’s marketing targets, not on speculation about 35 years hence — they spoke in remarkably consistent terms. Words like multidimensional, varied, flexible and collaboration kept coming up in interviews. The orchestra of the future will likely be smaller and play less. Subscriptions, while not disappearing entirely, will increasingly become a thing of the past.

“The concert hall with the two-and-a-half-hour concert is not what’s going to appeal 10 years from now, 15 years from now,” said Dawn Lipson, the chairwoman of the Rochester Philharmonic’s board, at a preconcert donors’ reception. Her orchestra, along with others small and large across the country, is experimenting with new special events, like next season’s “Video Games Live,” with arrangements of music from “Final Fantasy,” “Halo” and others. These programs are intended to appeal to new audiences, even though such programs pose a marketing challenge, lacking the buffer of guaranteed ticket sales provided by even a declining subscribership.