Once upon a time, in what seems now like a land far, far away, there was this magical, wonderful thing called AM Top 40 radio. True Top 40 radio, though its FM version persisted well into the '80s, saw its last real period of dominance in the '70s, before the rock audience was filleted, ever more thinly, by radio niche marketing and a record industry promotional switch from singles to albums. In 1972 or '73, for example, if you had a Top 40 outlet as grand as the one we had in Kansas City (WHB 710 AM), you might have heard Marvin Gaye, the Stones, Zeppelin, Charlie Rich, the O'Jays, Conway Twitty, Neil Young, Alice Cooper, Al Green, the Raspberries, Dylan, Elvis, Elton John, War, Sweet and more, all on the same station. Today these artists have been corraled into their respective oldies formats, but back then the music they made could all accurately be described as "pop" because it shared, over and above its many differences, a conviction that great singles -- with identifying instrumental hooks, hummable melodies, unabashed studio craft, and, if helpful to the song, full and dynamic arrangements -- were...well, great. Ten years old in 1972, I cut my musical teeth in this eclectic, singles-driven era, passing entire lazy afternoons just singing along with the radio and falling in love. Is it any wonder, then, that the pop charts of 1972, experienced just as I was first developing a self-conscious sense of my own taste, still provide a pretty fair representation of my core aesthetic, even as an adult? I can't say for sure, of course, but I'd wager that Joe Henry, who's barely a year older than me, and Wilco's Jeff Tweedy, who turned ten in 1977, experienced much of their own musical comings-of-age around '70s pop, too. Certainly all three of us (and anyone else around our ages, which is to say one hell of a big chunk of what amounts to the alt-country audience) know quite intimately what transpired next: Album-oriented rock exploded at just about the same late-'70s moment that punk hit, and in their wakes was left an increasingly fragmented rock landscape, including the expulsion from pop radio of virtually all twang as well as the rapid development of narrower and narrower formats. It was the rootsiest elements of one of these formats, college rock (later, "alternative"), that would eventually pave the way for Uncle Tupelo and what we now term alt-country, whatever that is. Time was, it didn't get much alt-countrier than Joe Henry or Jeff Tweedy. In fact, one way to trace the genre's current flowering would be to recall a 1993 tour Henry opened a string of dates for Uncle Tupelo. Henry's bassist at the time, Jim Boquist, first met Tupelo co-leader Jay Farrar on this tour, foretelling the eventual development of Son Volt. But the times they have a-changed. Henry and Wilco's latest albums -- Fuse and Summer Teeth, respectively -- are alternative country by past association only, a development that wasn't exactly unpredictable. Henry, for example, has already explored several distinct sounds over the years. He started out a little bit rock 'n' roll, and then, with the Jayhawks in tow, he was a little bit country, too; on his last album, 1996's Trampoline, he forged a moody, groove-based sound best realized on the title track, a rubbery-legged fever dream of loss and chronic ghosts. Fuse continues the Trampoline approach, but it's a better disc because the grooves, largely played with unexpected soufulness by assorted Wallflowers, have so much give in them, so much room to breathe deep, even as they close in claustrophobically around Henry's wracked characters. Produced by Henry and T-Bone Burnett (with additional mixing done by Daniel Lanois), the album sketches men who have seen love blow up in their face and are convinced it's about to explode again. The angels he feels around him in one track, for instance, aren't guardians so much as capricious prophets of doom; in another song, he's mocked by a looped "ha-ha" that laughs like a creepy Greek chorus. With their fatalistic and paranoid minds, the men in Henry's songs self-destructively proceed to realize their worst fears, promising the impossible, wanting too much, holding on to what's already departed. Even alone they seem unable to let go or move forward -- unable to do anything, really, other than love on with a passion that's so tactile and involuntary that it sometimes seems nearly biological. "I love you with my skin and teeth," he moans in one typically evocative phrase. It's the sound of Fuse, though, that's most compelling. The earliest tracks here are of a piece, generally, with Trampoline, but as the disc progresses, bits of early '70s pop spring to the fore. Quite a few of the cuts -- with their slinky, chicken-scratch fills and soulful rhythms built around conga-like beats and funky bass lines -- suggest spookier versions of Bill Withers' folk-soul-pop cuts such as 1971's "Grandma's Hands", or stripped-down Curtis Mayfield hits. The instrumental "Curt Flood", with its jazz-funk guitar figures and laid-back churchy groove, brings to mind any number of early '70s blaxpoitation soundtrack numbers. Best of all, from its opening chime-like trumpet to its soul groove and swelling string arrangement, "I Want Too Much" sounds for all the world like a kind of spare '70s soul: a lo-fi "Me And Mrs. Jones", or a subdued "Papa Was A Rolling Stone". Both of those singles (by Billy Paul and the Temptations, respectively) were huge pop hits in 1972, when Joe Henry was just eleven. Which is a weird coincidence, because, after all its subtle evocations of '70s soul, Fuse concludes with two songs that each reference a completely different type of 1972 pop masterpiece: Randy Newman's Sail Away. Henry's "Beautiful Hat" includes almost exactly the sort of muted and mournful horn charts (here provided by the Dirty Dozen Brass Band) that made the opening of Sail Away's title track so hauntingly seductive, and the closing "We'll Meet Again" draws on the early 20th-century pop music that inspired Newman cuts such as "Let's Drop The Big One Now". Henry's often raspy and low-key delivery, and his knack for ironic yet emotional character studies, only heightens the Newman comparison. And it makes me wonder: Could it be that whatever music's in the air when you come of musical age -- say, around nine, ten or eleven -- will inevitably determine, at least in part, the music you'll be drawn to the rest of your life? You can't push something like that too far, of course. Different strokes for different folks and, at any rate, so many repressed adults spend their lives believing maturity means rejecting childhood's joys that for some people the exact opposite might be more accurate. Then again, on Wilco's new Summer Teeth, the primary reference point I've identified is the Electric Light Orchestra. ELO's walking-in-quicksand ballad "Telephone Line" was a Top Ten hit the very summer that Jeff Tweedy turned ten. In fact, ELO leader Jeff Lynne's fingerprint is all over Wilco's latest, though that influence is never more explicitly cited than on the breathtaking pop of "Shot In The Arm": the spacey, swirling synths; the clipped, rhymed lines and booming timpani; the long, straight string lines that rise and rise, then deflate to a hush in slippery glissandos -- all of it would fit perfectly on ELO's A New World Record (1976) or Out Of The Blue (1977). Elsewhere on Summer Teeth, the ELO-isms show up more as isolated sounds: the metronome drive of "I'm Always In Love"; Jay Bennett's panting, calliope-styled organ on "She's A Jar"; the processed, almost steel-sounding guitars, or synths, or whatever they are, that kick off one song called, uh, "ELT"; and all those rubbery strings that show up everywhere (or are those actually synths programmed to mimic strings?). Throughout the disc, if you listen closely, you'll also hear other '70s references. There are real connections here to wonderful, keyboard-based singles by, among others, Eric Carmen, ABBA, the Babys, Queen -- all of whom, by the way, had significant chart success in 1976 and '77. For those who might be uncomfortable with such bubblegum-pop allusions, plenty of pre-approved pop references also are apparent. There's certainly a lot of solo John and Paul in the album, not to mention Magical Mystery Tour-era Beatles. There's a heaping helping of Pet Sounds/Smile-style Brian Wilson, and some late Big Star too, especially in the way "Pieholden Suite" keeps changing directions, all of them unabashedly sweet and fragile and beautiful. In the end, though, Summer Teeth, with its huge, synth-heavy arrangements and 48-track punch, is an unabashed late-'70s pop record through and through. Its main inspiration is post-Beatles pop as played in the final days of a pre-punk world, the kind of music made by insecure pop stars who hide on the backs of buses, misunderstood and waiting for their covers to be blown, admired by fans who are comforted to know they aren't the only lonely ones. Indeed, as it often was on much of the best '70s pop, loneliness is a constant theme on Summer Teeth. At one point, Tweedy advises on "How To Fight Loneliness", but the weariness in his voice (and the wistful organ and bass of Jay Bennett and John Stirratt, respectively) make it clear that he's not even fooling himself. Elsewhere, Tweedy's lyrics can swerve, even in the course of a single song, from romantic innocence to the most visceral poetry. Near the beginning of "Shot In The Arm", for example, Tweedy sings sweetly, "We fell in love in the key of C," but by the end of the bridge he's flat screaming: "Something in my veins, bloodier than blood." What that bloody mess is exactly -- addiction, abuse, crumbling relationships, terrifying loss -- flits in and out of view more than necessary, thanks to lyrics that tend to become increasingly abstruse as the album progresses. Early on, however, when Tweedy's details and metaphors are honed as finely as they've ever been, the songs have an intense, devastating power. And even when they don't, the album's sound keeps you listening close, in case they pay off. Whether at their sweetest (the lullaby "My Darling") or their darkest (very nearly everything else), whether Tweedy's vocals are echoey and processed or naked to the world, the songs are underscored here in stunningly dramatic fashion, presenting even the grimmest tales and the most harsh confessions in a lush and gorgeous pop language that always sounds as if there might still be one more last chance to hope...for the singer and his relationships, and for rock 'n' roll. Scanning the vast rock-soul-pop-country spectrum, Tweedy, Bennett, Stirratt and drummer Ken Coomer refuse to be bound; they will borrow whatever they damn well please, and reshape it into whatever combination they need, to make their music -- to make pop music. Like a great '70s Top 40 station, Wilco plays the hits, all of them, and they dare us to to sing along again, like we were still kids at heart.