The media covered it, the critics sang its praises, and the organizers went out of their way to book quality acts. But the Equinox Music Festival, a jazz fest based in Boston, somehow never managed to sell the public on its concert series, and this week, the festival shut itself down and cancelled all remaining shows. According to the festival’s president, “The early events were extremely poorly attended, and the remaining events had extremely poor advance sales. It just came to the point where we had to pull the plug and stop hemorrhaging money. It’s most unfortunate, because we had a really phenomenal lineup.”