Paunches, gray hair, and male pattern baldness weren’t the only sign that Jeff Beck’s fans are guys approaching or smack dab in middle age. The occasional clouds of marijuana smoke wafting through the Orpheum Theatre a week ago Tuesday were especially rich and fragrant — not from the kind of weed one can afford on a student or recent-grad budget. And that sweet, earthy incense was appropriate for the concert, which was an unreconstructed ’70s rock show held in the kind of venue where Beck’s delivered his greatest performances.

It was old-fashioned music halls like the Orpheum — where audiences of roughly 3000 can focus entirely on the stage — that Beck toured behind his first all-instrumental albums, the hallmarks Blow by Blow (Epic, 1975) and Wired (Epic, 1976), and recorded 1977’s Jeff Beck with the Jan Hammer Group Live (Epic). These days — after more than a decade of dalliances with session playing, rockabilly, and techno — he seems to be zeroing back in on his æsthetics from that era: lead-guitarist front and center, all night long, bathed in a wash of psychedelic arena-rock lighting as pyrotechnic as his bottomless bag of licks and tricks.

Too bad Beck’s not reaching for more of his compositions from that time, because back then he unveiled a melodic genius that he exercises sparingly today. Although his new You Had It Coming (Epic) offers ample proof that it’s still intact — especially in his mock-sitar excursion “Nadia” and the lovely dark-toned ballad “Suspension” — his Orpheum concert was instead full of whammy-bar braying, caustic-toned lead-rhythm patterns, staccato fragments of quickdraw riffing, and other sonic shenanigans that paled whenever he constructed an entire melody.

Of course, Beck’s hard-assed attack (he’s a youthful-looking 55) and four-piece band featuring Jennifer Batten’s pastel synth-guitar colors and note-for-note challenges were stunning. And nobody gets a grizzlier tone out of a Marshall half-stack. Plus the subtle beauty of his slide, along with the delicate shades of bent notes and pitch changes he achieved with his Stratocaster’s whammy, were usually marvels of delicacy.

But beauty and technique are different creatures. It wasn’t until the night had nearly ended that Beck made his brightest statement, a faithful version of the vocal melody from the Beatles’ “A Day in the Life” full of passing tones, slide variations, and other filigrees including a whorl of feedback that re-created the original’s sonic vortex finale. Such a perfect balance of musicianship and showmanship is rare — and the very best of what Beck can do.