A previously unreleased Eric Clapton acoustic jam is set for release next year. "Mississippi Blues" was recorded with Tim Duffy and will be part of Blue Muse, a compilation from the Music Maker Relief Foundation.

The recording dates back to 1995, when Duffy – who'd then only recently co-founded the foundation with his wife Denise – first met Clapton.

"This particular cut began with Eric playing a slow blues in the key of A, and I backed him up with my simple rendition of the piece 'Mississippi Blues' by Willie Brown," Tim Duffy remembered on the Music Maker website. "Eric knew the tune. I told him I learned it from a Stefan Grossman recording, and Eric knew the album."

You can listen to it below.

The Music Maker Relief Foundation is celebrating 25 years of support for traditional blues and folk musicians and their work. It reports placing 11,840 grants while helping more than 435 artists along the way. The first Music Maker artist was Guitar Gabriel, a bluesman with connections to Bo Diddley and Chuck Berry who'd never seen any royalties for music released decades before.

Mark Levinson, known for his high-end audio equipment brand, introduced Clapton to Duffy after the former Cream legend happened to be lunching at a bistro near Levinson's studio. Duffy said the discussion initially focused on the newly established Music Maker Relief Foundation.

Then, he added, "Eric noticed the 1930 Martin 00-18 sitting in the corner. He told us he had not played guitar in some months and he asked Mark if he could check it out. When Eric began to play, it was spellbinding and among the most amazing musical moments of my life. I picked up my guitar and quickly tuned it a half-step up to match his and began to play some back up guitar licks that I learned from Guitar Gabriel. After a few songs, Mark asked Eric if he would like to record a few songs."

Ranking Every Eric Clapton Album

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