It was just an offhanded remark about the wintry conditions outside, but it was tempting to read into Stephin Merritt’s pronouncement. “We’re depending on you for warmth,’’ he cracked at the top of the Magnetic Fields’ show Wednesday, the first of two nights at the Wilbur Theatre.
Warmth isn’t the first thing that springs to mind with Merritt’s songwriting. Here’s a guy who can write a love song whose chorus flashes a sweet smile only to bare its fangs: “Every hour kills a flower/I’m falling out of love with you.’’
Besides, the Magnetic Fields, which got its start in Boston in the early 1990s, doesn’t need much from its audience. The quartet - fleshed out on tour by longtime contributor Shirley Simms - trades on its familial vibe, to the extent of members talking more to one another than to the crowd. It’s as if the Royal Tenenbaums formed a band and took their deadpan act on the road.
In that case, Merritt was obviously the father figure, strumming his ukulele, drolly bantering, and trading vocal duties with Claudia Gonson, who also did a lovely job on keyboards, and Simms, who intermittently played an autoharp resting in her lap. None are exceptional vocalists, but they’re all effective singers. Merritt brought heart and soul to a tear-jerker take on “All the Umbrellas in London,’’ his baritone soft and his head bowed. Gonson mixed reverence and satire on “The Dolls’ Tea Party.’’ And Simms, ever the understated presence who kept her eyes trained on Merritt while she sang, was a well of warmth and humor on “The Nun’s Litany.’’ (She apparently didn’t want to sing the song’s lewd lyrics - “I want to be a porno starlet/ For that I’ll wait till Mama’s dead’’ - the next night because her own mother would be in the audience.)
The acoustic stage setup put the emphasis where it’s always been: on Merritt’s songwriting. John Woo had an occasional guitar flourish (especially on a pristine version of “Acoustic Guitar’’), and Sam Davol’s majestic cello accompaniment was integral on particular songs (“From a Sinking Boat’’).
By the time the band wrapped up with “100,000 Fireflies,’’ Merritt’s earlier request suddenly felt unnecessary. All the warmth he could have wanted was already emanating from the stage.
James Reed can be reached at jreed@globe.com. 
