The marriage of pop melodies and loud electric guitars is hardly new, but it is continually renewed; Husker Do did it in the mid-80s by making the noise rawer and the hooks catchier, and My Bloody Valentine did it more recently by distorting the guitars into a candied sonic morass. Bailter Space, a migratory trio that has called New Zealand, Germany, and the U.S. home, have been around quite a while (the same personnel, drummer Brent McLachlan and guitarists John Halvorsen and Alister Parker, played under the name the Gordons in 1980 and were renowned as New Zealand's loudest band), but on their new album, Vortura (Matador), they've perfected a new loud-pop variation. Their success hinges on a scientific application of massive volume; guitarists Parker and Halvorsen play so loud that the original notes become lost in enveloping waves of overtones. The effect can be lovely and soothing in combination with Parker's tender croon, or maniacally assaultive when Halvorsen takes the helm. Listen closely and you'll find the songs are surprisingly simple, often built around a single repeated phrase and propelled by a monster guitar hook. But then a structure has to be sturdy to support something really heavy. The single-minded concentration Bailter Space bring to bear on their songs in concert can seem mechanical, but it's also passionate and absolutely unforgettable. Bring earplugs. The opening acts are Pittsburgh's Karl Hendricks Trio, who encase their postgirlfriend laments in a satisfyingly chunky punk-rock sound, and Hardvark. Saturday, 10 PM, Lounge Ax, 2438 N. Lincoln; 525-6620.