some of my favorites

Paul Butterfield Blues Band..Mike Bloomfield is awsome..great solo on shake your moneymaker.

Anything by Blind Willie McTell is Amazing

Anything by Mississipi Fred McDowell

Howling Wolf-London Sessions- with Eric Clapton, Stevie Winwood, Bill Wyman, Charlie Watts.

Those are good to start with

There's so many it's easy to miss a lot.

Essential blues, hell that could easily turn into a thousand albums if you aren't careful!!
I would maybe suggest for someone who is just dipping a toe in the pool, so far, to head to HMV and pick up a few blues collection CD's.

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I'm not an expert, but I play one on the internet.