Pop-Rock Asia: "Alpha." (Geffen Records GHS 4008.)--Asia has calculated appeal, so carefully crafted is its brand of pop-rock. Its music, with a built-in resonance of rock stadiums and crowds cheering widly at music only roughly heard , strikes the powerful chord of drama in rock. It is at once exhilarating and state. Stale -- when much of it suggests a machine that, at the touch of a switch, will produce any tune sounding like an electric organ. Exhilarating -- in its audacity to produce melodramatic "corporate rock" in an era of subtraction. Subtraction, sometimes, of voice, synthesizer, and close-cropped melodies. For sheer top-40-hit power, "Don't cry" is built with eight cylinders. The song accelerates to a central theme that I found lingering with me long after the actual noise had zoomed off. One thing this British rock quartet with roots in the 1960s develops in this, their second album, is consistency. Consistency between albums, among songs -- even consistency in moods, though there are times when Asia seems to be quoting in sound from the Moody Blues and perhaps Kansas. Lyrics, for the most part, aren't much to speak of. Just something to hang John Wetton's powerfull vocals on. There are tales of deceit in love, everlasting, faithfulness, and so on. Pick any song and it will illustrate the meticulous Asian song pattern of building up to a central theme with a repeated phrase that's also the song title, reprise once or twice, then close. Its very conventional and, in this case, successful. This is the work of a band that's been in the rock-music industry for years and knows how to create grabby, lucrative rock. They succeed in that with splendor. Much more, they don't do.