During the Wednesday lunch rush at the Reading Terminal Market in Philadelphia, shoppers were surprised by a sudden onslaught of saxophones.

In a dining area in the middle of the market, surrounded by turkey sandwiches and pulled pork, two drummers set up a conga and a kit. While they laid down a rhythm, six saxophonists entered from six market entrances, blowing their horns.

Separated by hundreds of feet and hundreds of people, the sound came out like a discordant jam. Once they converged in the center of the market, saxophonist Sam Reed counted off the beat for "Tenor Madness," a song recorded in 1956 by Sonny Rollins, his only collaboration with John Coltrane.

"Sonny Rollins and John Coltrane — although the public thought they were enemies and competitors, but they were actually really good friends and enjoyed hanging out together," said Homer Jackson, the director of the Philadelphia Jazz Project and the coordinator of this pop-up concert. "It showed their camaraderie and unity as musicians, and we wanted to show the same thing."

April is Philadelphia Jazz Appreciation Month (Philly JAM) with more than 350 jazz events scheduled throughout the Philadelphia region. For the pop-up concert, Jackson pulled together some of the area's top talent, including Reed, Elliott Levin and Tim Price.

Listeners could easily hear the players' different styles as they traded solos on "Tenor Madness." Price had a bright, clean sound while Levin worked a harder growl. It is rare to hear these guys play side by side

"People have been saying jazz is dead since its birth," said Jackson. "The musicians are as excited as they were 75 years ago, and audiences respond to it the same way they did 75 years ago."

The performance instantly attracted a crush of listeners with cell phone cameras, including a group of high school students visiting from San Diego on a class trip. They had stopped at the market for lunch on their way to the Liberty Bell. The jazz concert stopped them in their tracks.

Fifteen-year-old Martina Lopez and 17-year-old Carlos Bueno paused during their lunch stopover at the market.

"I liked it a lot," said Bueno. "The melody was great and the harmony was great, solos were very impressive."

"The last harmony between the instruments was, like, ahhh!" said Lopez. "It was wonderful."

After the performance, Bueno grabbed a reporter to play some jazz soundtrack work by composer Michael Giacchino loaded on his cell phone, and novelty jazz-pop mashups by Scott Bradlee, suggesting that reports of the death of jazz have been greatly exaggerated.