In many ways, Blonde Redhead bear little resemblance to the Sonic Youth-inspired band that exploded onto the post-rock scene in the mid-90s.

The Blonde Redhead of yesteryear were a force to be reckoned with on stage, with front woman Kazu Makino’s blood-curdling screams and guitarist Amedeo Pace’s jigsaw guitar work always keeping the listener firmly on edge. But a lot has changed since the band’s formative years, and its present incarnation favors airy melodies over atonal chaos and electronic ambiance over electric guitars. As the crowd gathered to watch the trio at House of Blues on Sunday, it was treated to something that was much more soothing than scathing.

Following a set of polite folk from Icelandic solo artist Ólöf Arnalds, Blonde Redhead took to a stage that was shrouded in ethereal light and artificial fog. Makino, wearing a horrific mask that resembled some kind of bearded sea fossil, purred and cooed over each song with her disembodied vocals. Like fellow New York art-rockers Yeah Yeah Yeahs, the band has made a decided shift from guitars to synthesizers in recent years. At times, Makino, Amedeo, and even an anonymous touring musician all played synths at once, with Simone Pace’s drums serving as the only odd instrument.

Not that Simone’s kit sounded organic. His drums were processed just as much as the other instruments, but his fluttering beats gave the songs much of their energy. Unfortunately, because the band stuck close to the inessential new album Penny Sparkle, energy was on short supply. But whenever Blonde Redhead did play their less-recent material, such as the guitar-heavy “Spring and By Summer Fall,” the ominous “Falling Man,” or the classic “In Particular,” the electronic chill quickly thawed.

Moments like those were all too rare, and it was never long before things iced over again. The best part of the performance was actually the blistering encore, which found the band finally cutting loose with three of its best songs — “Equus,” “Melody Of Certain Three” and “23.” It was a thrill to see the group forsake synthesizers in favor of guitar and bass, and Makino even ended “Equus” with one of her signature tea-kettle screams.

The evening’s iciness never distracted from the fact that Blonde Redhead are brilliant musicians and consummate performers. Every note, no matter how sedated, was played with confidence and grace. But the band seems determined to place layers between itself and the audience — whether it be stage fog, Makino’s mask, or the abundance of otherworldly effects — and the result is often impenetrable when it should be moving. The trio is meticulous in crafting its art — even the lighting design was incredible — and nothing it does is ever accidental. As such, it’s tempting to give Blonde Redhead the benefit of the doubt, but it’s also hard not to pine for the days when their music was as visceral as it was cerebral.