Alex Chilton, whose ’60s fame as lead vocalist for the hit-making pop band the Box Tops was succeeded by leadership of the massively influential ’70s group Big Star, died Wednesday in New Orleans of an apparent heart attack. He was 59.

Born Dec. 28, 1950, in Memphis, Chilton was the preternaturally mature voice of the Box Tops, a Bluff City group that was deeply influenced by the city’s contemporaneous deep soul. Produced by Dan Penn, the group found instantaneous success with a smash version of cleffer Wayne Carson Thompson’s “The Letter,” which roared to No. 1 on the national charts in 1967. Chilton was just 16 when the single hit the top.

The Box Tops toured heavily and notched a handful of lesser hits – including “Cry Like a Baby,” “Neon Rainbow,” “Soul Deep” and “Sweet Cream Ladies,” probably the only chart record of its day about prostitution. But Chilton tired of the grind and the band’s music, and, abandoning the group in 1970 after four albums, he moved to New York to reconsider his career.

After a year, he returned to Memphis and began working with singer-guitarist Chris Bell, a former member of the local bands Icewater and Rock City and a devoted acolyte of the Beatles. The pair and their rhythm section, bassist Andy Hummel and drummer Jody Stephens, had virtually unlimited access to Ardent, a state-of-the-art local studio built and operated by engineer John Fry. Named after a market that stood near the Ardent facility, the band was known hopefully as Big Star.

The quartet’s optimistically titled debut album, “#1 Record,” was released in 1972 on the Ardent imprint, which was distributed through the prominent Memphis soul label Stax. The alternately blissful and hard-rocking pop songs on the set, written by Chilton and Bell, were worthy of comparison to the work of Big Star’s Liverpudlian models; in 1973, they impressed a full house of music journalists at the first Rock Writers Convention in Memphis (an event set up by Ardent’s head of promotion to wine and dine top rock critics).

However, Stax’s distribution deal with CBS Records was hitting the rocks just as Big Star’s bow was issued, and “#1Record” was little heard outside the Mid-South. Frustrated and depressed by the band’s failure and facing escalating conflict with Chilton, Bell exited the group; he died in 1978 in a single-car accident in Memphis.

As Big Star’s lead vocalist, songwriter and sole guitarist, Chilton completed two more albums under the group name. “Radio City” (1974) was a trio recording with Hummel and Stephens that is nearly the equal of the band’s debut, but it suffered the same commercial fate as its predecessor. A third collection – alternately known as “Big Star Third” and “Sister Lovers” – was cut under chaotic circumstances by producer Jim Dickinson, with Chilton, Stephens and an oddball crew of locals interpreting a bizarre and unsettling set of originals and covers; it saw belated release in 1978 on indie distributor Jem Records’ PVC label.

For nearly two decades, Chilton abandoned Big Star for a solo career that moved forward and backward in fits and starts. He issued several idiosyncratic solo albums – many of them live — on independent labels in the U.S. and abroad; the most distinctive of them may be 1979’s “Like Flies On Sherbert,” another shambolic record much in the manner of Big Star’s third.

Big Star’s profile began to rise in the late ’70s, after EMI in England reissued the band’s first two Ardent LPs as a two-record set. The group would have a pronounced impact on the sound of such disparate ’80s indie-rock acts as R.E.M. and the Replacements (who recorded the homage “Alex Chilton”), while the all-girl L.A. rock act the Bangles paid tribute by recording Chilton’s “September Gurls.” In the ’90s, the band’s “In the Street” became the theme song for the Fox sitcom “That ’70s Show.”

Though Chilton appeared on the indie club circuit, he would remain a contrarian figure and a reluctant interview subject who was clearly uncomfortable with discussing his ’70s work. He lived in New Orleans in the early ’80s, and subsumed himself as a sideman and producer of Tav Falco’s group the Panther Burns.

In 1993, after receiving a request to play a show on a college campus in Missouri, Chilton and Stephens regrouped as Big Star with two avowed fan-boy sidemen, Jon Auer and Ken Stringfellow of the Seattle pop band the Posies. The show was recorded and issued by RCA-distributed Zoo Records as the album “Columbia,” and began years of on-and-off concert dates with the renewed lineup. The band also recorded a coolly received album of new material, “In Space,” with Memphis producer Jeff Powell for Rykodisc in 2005. Last year, Rhino Records issued a lavish boxed set “Keep An Eye On the Sky,” that compiled both familiar and unreleased Big Star tracks from the Ardent era.

Beginning in 1989, Chilton rejoined the former members of the Box Tops for infrequent concerts. While his writing and playing with Big Star is the rock upon which his reputation is built, Chilton always appeared to be having more fun playing with his first band.

In a strange curiosity of timing, a panel focusing on Big Star with Stephens, Auer and Stringfellow – but not Chilton – is scheduled for Saturday at the South By Southwest Music Conference in Austin.

Drummer Stephens said Thursday that the band members will proceed with plans for a Big Star performance at the fest on Saturday. Musicians in town for SXSW are being solicited to fill in for Chilton.