Though not as romantic as a candlelit dinner for two, the Magnetic Fields’ concert at the Somerville Theater last Thursday was clearly a Valentine’s Day celebration of sorts, consisting of two impressive sets played to an audience filled with couples. Stephin Merritt, the band’s singer and songwriter, used the occasion to add another layer of irony to his lyrics. Though he was mostly quiet between songs in the first set, Merritt seemed to become more comfortable with stage banter in the second half of the show. “Valentine’s Day is in the middle of February so that anyone without a date will freeze to death,” he quipped. “How Darwinian.” His dry, somewhat misanthropic sarcasm provided a refreshing contrast to the otherwise sappy holiday.

As with any indie show, tight jeans and black plastic glasses were omnipresent. In this case, however, they were worn almost entirely by older (read: post-collegiate) people. This is partially because the Magnetic Fields have been around since the mid-nineties, but it also seems to be a function of the venue. Somerville Theater has found a unique niche market, catering to a somewhat older demographic with established indie artists who haven’t “sold out.” While the band was kept to a fairly low volume, everyone sat politely until the last note of each song stopped ringing.

Though songs from “Distortion,” the band’s newest album, are covered in layers of shoegaze distortion, feedback, and electronic effects, the live performance was entirely acoustic, consisting of piano, guitar, cello, and bouzouki (an eight-stringed instrument similar to a mandolin). Adapting the new songs to this format consisted mostly of removing drums and guitars to expose the melodies underneath. Merritt’s latest lyrics emerged from the layers of guitar noise to reveal a sincerity and intimacy unheard since “69 Love Songs.” Compared to the pristine, stripped-down acoustic versions, the studio recordings from “Distortion” sound cluttered and muddy.

The band’s earlier material, however, features digital and analogue synthesizers in many of the lead parts. In the absence of electronics, the cello and guitar were left to fill these voids. John Woo, the guitarist, adapted particularly well, using various picking techniques and a glass slide to approximate the synth lines of earlier Magnetic Fields albums. The cello was coated in crisp, low-frequency reverb that took full advantage of Somerville Theater’s excellent acoustics. Bass notes seemingly resonated forever, and higher parts sounded full and organic.

Merritt played mostly rhythm on the bouzouki, sharing lead vocals with pianist Claudia Gonson and Shirley Simms, the band’s new singer. Claudia’s upright piano was padded to muffle high-frequency resonance, yielding full but unobtrusive background chords and soft, understated scraps of twee melody. Individually, Shirley, Claudia, and Merritt are quite capable vocalists; together, however, they are far more than the sum of their parts. Their voices are perfectly suited to three-part harmonies: Merritt’s dry baritone, Claudia’s full alto, and Shirley’s crisp soprano melt together into a single uncluttered voice covering practically the entire harmonic range.

The acoustic set gave Merritt an opportunity to reformulate his work for a new environment, but he generally stayed true to the original songs. The arrangements were simple without being boring; Merritt’s lyrics were favored over musical experimentation. This has always been part of the appeal of the Magnetic Fields, and this performance showed that Merritt still has the lyrics to pull it off.