Members of the 1980s band, Operation Ivy, reunited to perform their signature song, “Sound System,” at the Musack Rock n’ Roll Carnival in Los Angeles. The performance came as a surprise to everyone, when Tim Armstrong was slated to play backup for the Specials at the festival already, and Jesse Michaels came out from the audience to join him.

In the video, which is available to watch below, the duo sang the spirited song, while being supplied even more energy from the audience. Surrounded by flashing lights, Operation Ivy performed their most popular song just as well as when it initially debuted.

The Musack Rock n’ Roll Carnival took place February 4 and February 5, and works towards providing more instruments to kids. In the 10th annual festival, The Specials performed with backing from Armstrong and members of the Interrupters, among others.