My most comfortable chair "now" is a well made Director’s chair and though I can still walk my back has been a painful mess from the early 80’s.
I’ve owned 2 Eames chairs and neither were comfortable.
Before - my most comfortable chair was a vintage heavy wrought iron folding chair (called French Riviera chairs in the ID trade) but things changed and it doesn’t work for me anymore.
With your back you really need to take a test drive before purchasing a chair.
Oh, and here's my standard recommendation (joke) for those long listening sessions...
DeKay