But first, Muscle Shoals - the name alone is plenty evocative to any follower of soul music. Out of the northwestern corner of Alabama - where Oldham was born and raised - came a rawer, danker take on Southern soul, chipping away at the glossier elements of R&B and replacing them with sweat and grit and - dare I say it? - a "jammier" approach to songcraft.

Also called "deep soul," the Muscle Shoals sound revolutionized soul music as we know it, and Oldham was a key player, not only laying down crucial organ tracks to countless classics, but also co-writing a few in the process. As part of Rick Hall's legendary Florence, Alabama FAME Studios' dream team - which also counted key session players Jimmy Johnson (guitar), Junior Lowe (bass), and Roger Hawkins (drums) as members - Oldham juiced up Percy Sledge's immortal "When A Man Loves a Woman" with haunting organ fills which lent the song a gravitas worthy of Sledge's impassioned vocal. From there, he and the FAME Studios band went on to heap serious soul-testimony to records such as Wilson Pickett's The Wicked Pickett (Atlantic), a raucous collection that found the band providing appropriately fiery accompaniment to Mister Mustang Sally's full-throated screams and shouts. The album, by the way, also boasts two shining examples of Oldham's then-recent songwriting partnership with singer-songwriter-guitarist and equally influential soul player Dan Penn: "She Ain't Gonna Do Right" and "Up Tight Good Woman."

Upon moving to Memphis, Oldham's session schedule picked up an additional notch or two. Meanwhile, his songwriting union with Penn was proving to be a mighty partnership. Over the years, the Penn/Oldham collab proved quite fruitful, to say the least: two instant-classics which come to mind are James and Bobby Purify's "I'm Your Puppet," the Box Tops' "Cry Like a Baby," and Janis Joplin's incendiary weeper "A Woman Left Lonely" (the latter of which was given an intriguing makeover on Cat Power's aforementioned Jukebox).

Then, of course, there was Aretha Franklin's I Never Loved a Man the Way I Love You (Atlantic), the Queen of Soul's (unless you ask Beyonce, apparently, if you want to make bones about the Destiny Child's recent Grammy gaffe) breakthrough masterpiece and an absolute must-have soul music landmark.

Produced by the masterful Jerry Wexler, the album was the first in Aretha's career to truly tap into the blazing intensity with which we now associate the vocalist. Prior to this Atlantic debut, her Columbia recordings suffered slightly from a sense of restraint and over-politeness. Wexler knew he needed the right musicians to spark the singer's fires within, and he found them in these Muscle Shoals players, including Oldham.

It's hard to fathom soul-stirrers such as "Do Right Woman, Do Right Man" and "A Change Is Gonna Come" without his gospel-fervor accompaniment, and his playing on the title track set the standard for understated (but authoritative) soul-organ declarations. Oldham's ivory-tickling know-how continued to deliver drama to other Aretha masterpieces, including the one-two punch of 1968's Lady Soul and Aretha Now and the following year's equally-wowing-but-sadly-underappreciated Soul '69 (all Atlantic/Rhino) .

With the arrival of the '70s, Oldham relocated to Los Angeles and became a much sought-after session musician, bringing Deep South soul to records by Bob Dylan, Linda Ronstadt, and Joe Cocker, among others. He also became part of Dylan's touring band in the early '80s, during Dylan's heavy-handed Christianity-conversion period.

Fast forward a couple of decades, and Oldham has experienced quite the renewed attention on his singular technique, starting off with his elegant piano and organ phrasing on Neil Young's 2005 acoustic gem Prairie Wind (Reprise) and the album's subsequent 2006 Jonathan Demme concert film Heart of Gold. Last year brought Bettye LaVette's take-no-prisoners stomper The Scene of the Crime. The title, by the way, is a not-so-veiled reference to Muscle Shoals, Ala., the site of a 1973 album which was inexplicably scrapped by her record company and never released. (Other than on bootleg editions, that is, until 2006, when Rhino issued the scorcher under the title Child of the Seventies).

Oldham's piano and Wurlitzer work on The Scene of the Crime brings plenty of righteous "you-tell-it" backup to LaVette's snarling, sneering delivery, and his immersion into the late-night soundscaping of the Drive-By Truckers - LaVette's backing band on the album - creates the impression that the guy's an auxiliary member. (Which, it turns out, he essentially is - more on that soon)

Take LaVette's cover of Willie Nelson's "Somebody Pick Up My Pieces," for example: Oldham's closing-time barroom piano is pure Southern countrified gospel, albeit filtered through too many whiskeys and boozy lighting. Or how about the moody-as-hell "Jealousy," on which Oldham heaps brooding, stalking Wurlitzer drama underneath LaVette's wrenching delivery? Much has been made of the Drive-By Truckers' intuitive accompaniment - and for good reason - but Oldham's contribution cannot be mentioned enough.

Speaking of the Truckers, Oldham's role here is also monumental - hence his honorary-member status, as well as the fact that this year's thoroughly-engrossing epic Brighter Than Creation's Dark is dedicated to him. Band leader Patterson Hood, on the Truckers' official Web site, describes him as "the single most creative soul I have ever met." On the off chance you might need more than just testimony from a leader of perhaps the most important band currently operating from the South, may I suggest heading directly to Dark's "Daddy Needs a Drink," a moving portrait of a dysfunctional household made all the weepier by Oldham's tender interplay with the aching sighs of pedal steel guitar. Or maybe Oldham's sunny-glow organ work on the boot-stomping anthem "Self Destructive Zones" (which name-drops Muscle Shoals) might be just the confirmation you need.

And here we are, not only two months deep into 2008, and we have ourselves a double-dose of Oldham wizardry! Cat Power's recent covers collection Jukebox also shows off the deeply soulful organist at the top of his game. Opening track "New York" benefits from rolling, bubbling electric piano phrasing, for example. It's especially interesting, though, to witness the interpretation of "Woman Left Lonely," the Penn/Oldham composition originally written for Janis Joplin. The original version's elegant-but-earthy presentation seems to have largely informed the entire full-length's compelling, understated, after-hours soul ambiance, and while that might not be quite the same as receiving an LP-dedication, providing the template for a work of such ravishing beauty as Jukebox surely must count for a whole hell of a lot, too.

Oh, and one last thing: guess who laid down all those fine, fine twinkling heartbroken melodies on James Carr's shiver-inducing melodrama "The Dark End of the Street"? That'd be Spooner, of course.