LEHAR: "DER ZAREWITSCH." Lucia Popp, Elfriede Hoebarth, Rene Kollo, Norbert Orth, Ivan Rebroff; Chorus of Bavarian Radio; Munich Radio Orchestra conducted by Heinz Wallberg. Eurodisc 610 137-232 (two compact discs). Popp's enraptured performance of the familiar "Einer wird kommen" transcends the fripperies of this delectable 1927 confection about the fairy-tale crown prince torn between love and duty, a conflict that spreads from Russia to Naples, and is conveniently resolved by an off-stage death. Kollo swaggers ebulliently through the "Volgalied," but the persistent beat in his tenor lessens romantic appeal. Eurodisc's recording sounds like a studio effort without much theatrical ambiance. The supporting cast isn't much, and Rebroff's gruff bass sinks below even acceptable operetta standards despite the fact that this edition assigns him extra music. OK sound; much dialogue; no libretto; notes in German only.