James Blake has the element of surprise working for him. The 22-year-old Londoner first became known last year as a producer of dubstep, the British club-music micro-genre marked by throbbing, reverberating bass.

But that was "a long time ago," Blake said on Monday night during his first Philadelphia performance, at a sold-out First Unitarian Church, where the show was moved to from Johnny Brenda's to accommodate demand. "Well, not that long. But you know how the Internet is."

Yes, we do. The Internet is a place where an evolving artist can grow up, and be scrutinized, in public long before putting out a full-length album. And when he does put out an eponymous full-length - as Blake did, in January - he can generate even more buzz by displaying talents more multifarious than those that dweeby, techno, knob-twiddlers are expected to possess.

In Blake's case, that means he not only knows how to manipulate his voice using digital effects, he can also sing. Quite beautifully, thank you. Bathed in blue light while sitting at the keyboard in the church basement, where he was backed by a drummer and a guitarist who also triggered samples on a laptop, Blake sang in an incantatory, sensitive, soul man style that bears a similarity to fellow indie sensation Antony Hegarty of Antony & the Johnsons.

Blake, who studied music composition at the University of London, has a practiced ear for material well suited to his sensibility. His signature song is a ghostly, deconstructed cover of Leslie Feist's "Limit to Your Love," and on Monday a rowdy crowd drew him back on stage for what might actually have been an unplanned encore for a gossamer solo piano version of Joni Mitchell's "A Case of You."

Blake has more than good taste going for him. Though his songs rarely conform to conventional structures, they display a familiarity with gospel chord changes and dub-reggae dynamics. Like Radiohead and 1990s trip-hop acts such as Portishead, Blake is skilled at using silence and empty space, along with glitchy, rickety percussive effects, to create drama in his almost-always down-tempo tunes.

He sometimes can sound like he's ready to tumble into the abyss: "My brother and my sister don't speak to me, but I don't blame them," he sang repeatedly, dueting with a digitally altered and looped version of his own voice on "I Never Learnt to Share."

But in an hour-long set, Blake demonstrated that his audience-relating skills have improved considerably since he performed in March at the South by Southwest Festival in Austin, Texas. And the depressive tendencies in Blake's highly emotive music were balanced by the lush textures that cushion his languorous tunes, as well as the promise of a bright future that clearly lies ahead.