Jason Isbell And The 400 Unit Band Members. Hart, the band’s bassist, shared the news. At its essence is a psychologically splintered cast of characters, found on highlights like.

Jimbo hart, who has played bass in jason isbell & the 400 unit since the group’s formation in the late 2000s, has announced he’s parting ways with the group,. Paul on saturday and sunday suggested a lyric in their song, “if you insist,” the swirling combination of music.