A few years ago after a show in Seattle, singer-songwriter and former computer programmer Jonathan Coulton was approached by two developers from multi-billion dollar videogame empire Valve Corporation. Agreeing to work with them on their new project, Coulton wrote “Still Alive”, the song which closed Valve’s 2007 puzzle game Portal. Featuring the vocals of a deranged artificial intelligence played by opera singer-turned-voice actress Ellen McLain, the piece drew on Coulton’s experience with geek culture and added millions of gamers to his expanding audience. Given the break of a lifetime, what is a self-described “internet superstar” to do next?

His first full-sized release of new material since 2006, Artificial Heart aims to cover a lot of bases for Coulton. Featuring production by the most ideal candidate, John Flansburgh of They Might Be Giants, the record is a bold effort to not only energise Coulton’s existing fanbase but also to broaden and professionalise his sound in a way which might attract new and more mainstream listeners. This enterprise is not without risk – broadened horizons mean scaled-down geekery from Coulton, who has expressed a fear that his existing devotees might react negatively to even a modest change in style. Rarely has an album of slick power pop walked such a precipitous tightrope – these are tense times for “JoCo”, but deliciously exciting ones for those of us on the outside.

A quick look at the track listing reveals big changes: on the sweet and simple “Nemeses”, vocal duties are deferred to John Roderick of the Long Winters, Suzanne Vega duets on “Now I Am An Arsonist”, and Sara Quin of Tegan & Sara has the unenviable task of replacing McLain on a new version of “Still Alive”. Significantly, Artificial Heart sprawls at a huge 18 songs. Coulton fans will no doubt celebrate this surfeit of new material, but those looking for a consistent listen may be disappointed: during 2006, the singer recorded and released one song every seven days for his “Thing a Week” project and this seems to have instilled in him a lack of self-editing which Flansburgh has not entirely curtailed.

In any case, there are a stack of inarguably great songs to be enjoyed here. While Coulton still hops styles with confidence and verve, his core power pop sound is thicker and more refined under Flansburgh’s direction. The title track and the gleeful “Sucker Punch” stand out among the rockier fare, while “The World Belongs to You” holds the torch for Coulton’s folk side: although musically a pastoral stroll, the song could be interpreted as the story of the power players who learn that the world is turning against them. “From inside these limousines the world is looking darker every day,” Coulton mourns, “and you wonder if that means when you close your eyes it goes away.” Simple and affecting, it’s a terrific piece of songwriting whichever way you slice it.

All this is a world away from the robots and mad scientists of some of Coulton’s older work, of course, but our man has been careful to preserve a humorous streak. “Alone at Home”, for example, is a wry and genuinely funny look at the tasks men endure for the sake of their girlfriends. Unfortunately, Artificial Heart also preserves a few genuine clunkers which ought to have been left on the operating room floor. Most noticeably it is hard to see “Today With Your Wife” as anything other than an unmitigated disaster - a dropout from the Stevie Wonder school of piano balladry, it’s a leaden, mawkish nightmare which jars horribly with the rest of the album. One or two other tracks are as eminently skippable, but less easily avoided is the pompous instrumental buildup to “Still Alive”, which when it finally arrives is a weak cousin to the original.

For each of these disappointments, though, Coulton serves up at least two genuine gems. A little inconsistent it may be, but Artificial Heart is one of the most replayable albums of the year which, in combining Coulton’s songwriting smarts with Flansburgh’s emboldening influence, produces something frequently irresistible. “JoCo” might have returned with “Want You Gone” for Portal 2 this year, but if there is any justice it is Artificial Heart which will take him up a level.

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