Circles Around the Sun visits the Domino Room Sunday.

Bands form for all kinds of reasons — out of boredom, over shared interests, because some songwriter has something to say and so on.

But how many bands form specifically for the purposes of creating intermission music for a series of reunion concerts played by the surviving members of the Grateful Dead? Just one: Circles Around the Sun, an instrumental quartet that continued on its own after its initial gig — the 2015 shows celebrating the Dead’s 50th anniversary — was up.

Guitarist Neal Casal formed Circles Around the Sun to play sprawling, psychedelic jam-rock that echoes the Dead, and the band has delivered, recording three albums full of exactly that. The latest — 2020’s self-titled effort — was “a welcome sonic elixir from the distressing realities” of our current times, according to PopMatters. Sadly, it was also the final Circles album featuring Casal, who died by suicide in August of 2019. The songs on “Circles Around the Sun” represent the final studio work of Casal, who played with Ryan Adams, the Chris Robinson Brotherhood and Hard Working Americans, among other well-known bands.

According to the band’s website, Casal left behind a note asking his three band mates in Circles Around the Sun to continue without him. They’ve done that, and this weekend, they’ll bring the project to Bend for an evening of delectable jams.

Circles Around the Sun: $17; 8 p.m. Sunday; The Domino Room, 51 NW Greenwood Ave., Bend; bendticket.com.