McDuff was a late starter on the organ — he came to it after playing bass, and that background shows. His left hand lays down bass lines with a locked-in authority that most organists never quite manage. There's a physical weight to his playing, a sense that the music is rooted in something low and solid before it goes anywhere else. If you put on Tough 'Duff (1960) and aren't moving in the first thirty seconds, check your pulse.

He's probably best known for giving George Benson one of his earliest significant gigs, and Benson sounds fantastic in that context — young, hungry, and perfectly matched to McDuff's earthy attack. But it would be a mistake to think of McDuff mainly as someone who launched other people's careers. His own recordings from the early-to-mid sixties for Prestige are some of the most satisfying organ-combo jazz on record, full of blues feeling and genuine swing without ever tipping into schmaltz.

The organ-combo format was everywhere in the early sixties, and McDuff was one of the players who helped define what it could sound like when it had some backbone. He wasn't interested in prettiness. His ballads are tender but never soft, and his uptempo burners have a road-worn quality — like music that had already been played in a hundred small rooms before it hit the studio. Brother Jack (1960) captures this perfectly. It's not flashy. It's just really, really good.

By the seventies, McDuff adapted to the times with varying results, moving toward funk and soul-jazz crossover territory. Some of it holds up, some of it feels dated, but even when the arrangements get a little thick he tends to cut through with that instantly recognizable tone — that deep, slightly dirty Hammond sound that he had locked in from the start. He was never chasing trends so much as absorbing whatever was useful and discarding the rest.

He kept working well into the nineties, recording for Concord and staying on the road. Later recordings like Color Me Blue (1997) show him relaxed and confident, without any sense that he had anything left to prove. The fire was a little lower, but the feel was still there. McDuff is one of those players who rewards going deep into the catalog — the more you hear, the more you appreciate how consistently he delivered the thing he was actually trying to deliver.