Bassist Jimbo Hart Leaves Jason Isbell’s 400 Unit

photo: via Jimbo Hart on Facebook


One of the long-time members of Jason Isbell’s backing band The 400 Unit has officially left the outfit. Bassist Jimbo Hart has been part of the 400 Unit since the official formation of the band after Isbell left the Drive-By Truckers, but Jimbo took a hiatus earlier this year citing mental health concerns. Now he’s announced that he is officially no longer a member.

On June 4th, Jimbo Hart said via social media, “Hey y’all, you won’t see me for the first week of this next tour. I’m taking some time to take care of my mental health and resolve some old-school traumas. Thank you, Jason Isbell for giving me the grace and space to allow this process.”

Fans noticed that even after the initial absence, Jimbo did not return. Bass players Anna Butterss, Dominic John Davis, and Cat Popper have been filling in during the interim.

Then on November 27th, Jimbo Hart confirmed, “I’m no longer a member of the 400 Unit. I’m grateful for all the years, all the faces I’ve played for in the course of the band’s history and proud of all we accomplished. I’m happy to be moving forward into a new chapter of life and open to all possibilities, as they may arise.”

Jason Isbell said in a statement on November 28th, “I love Jimbo and I’ll miss touring and playing with him. Very glad he’s taking care of himself. Everything else anybody needs to know is in the statement he released.”

Originally from Sheffield, Alabama near Muscle Shoals, Jimbo Hart was recruited by Jason Isbell out of the Rolodex of the region’s world famous studios. Hart appeared on the eponymous Jason Isbell and the 400 Unit in 2009, and has appeared on every 400 Unit album since, racking up four Grammy Awards, and multiple nominations for the band’s 2023 album Weathervanes.

Hart has also appeared on albums from Drayton Farley, Morgan Wade, The Bahamas, Josh Ritter, and fellow 400 Unit members Sadler Vaden and Amanda Shires, among others.

A recent press photo of Jason Isbell and the 400 Unit featured bassist Anna Butterss with the band, leading to speculation that she will be the permanent fill-in. From Australia, she has also played with Phoebe Bridgers, Jenny Lewis, Madison Cunningham, Bright Eyes and Aimee Mann over the years. Butterss also performed during Isbell’s recent appearance on Austin City Limits.

The 400 Unit has also been featuring Will Johnson on the backline recently playing acoustic guitar and drums/percussion. Johnson was previously the lead singer of the Denton, TX-based band Centro-matic.

The 400 Unit is named after the psychiatric ward of Eliza Coffee Memorial Hospital in Florence, Alabama, which has since been renamed the Behavioral Health Center.

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