Donaldson grew up in North Carolina absorbing the blues and gospel that were simply in the air, then moved north and fell under the spell of Charlie Parker. That combination — Southern roots plus bebop architecture — runs underneath almost everything he recorded. You can hear Parker's fingerprints in the fluency of his lines, but Donaldson never sounds like he's doing an impression. Something earthier is always pulling at the music.
His early Blue Note sessions from the 1950s find him in full bebop mode. Blues Walk (1958) is a masterclass in playing the blues at tempo — cheerful intensity that never tips into showing off. He was central to the hard bop scene of that period, not peripheral to it.
Then came the turn. By the late 1960s he was leaning into organ combos and a funkier pocket, riding the soul jazz wave Blue Note was cultivating. Alligator Bogaloo (1967) is probably his most famous record from that stretch, and it deserves the reputation — loose, bluesy, almost shamelessly fun. Some critics at the time read the shift as a step down. That reading misses how much real musicianship holds the groove together.
His tone — warm, a little husky, never piercing — and his conversational phrasing served him equally well in both modes. He was still performing into his nineties, which says something about his relationship to this music: it never looked like work. Full catalog on his artist page.