Chris Isaak is such a polite romantic you just know he wipes the tears right off his pillow so they won't stain the fabric. To him, unrequited love is more than a mere obsession; it's a fashion statement. Listening to the desert-dry odes to unfulfilled desires and broken hearts on San Francisco Days, it's easy to imagine Isaak, wracked with romantic despair, glancing in the mirror just to make sure every hair is in place.
Isaak has sustained that moody romanticism over three albums (and the subtly ear-catching ''Wicked Game,'' his left-field 1991 winner). San Francisco Days barely alters the formula; one song, ''Can't Do a Thing (To Stop Me),'' even sounds like a color Xerox of the earlier hit. For the most part, Isaak dreamily croons lines like ''I still love you/I still want you/I still need you,'' ''I love you so much/I love you too much,'' and ''All the good hearts have been taken'' to the echoey, mild-mannered twang of his band, Silvertone. The music is as well crafted as rich Corinthian leather, but it can also be stiflingly monotonous. He doesn't pump much life into a cover of Neil Diamond's great, sulking '60s hit ''Solitary Man,'' either. Maybe ''Song Sung Blue'' would have been a better choice. B-