The graduation from the acoustical to the electrical recording method in the 1920s remains the single most significant advance in the history of recording techniques. This doesn’t mean, though, that it was an unalloyed boon in its early days. In an unusually extensive and informative booklet note, Ward Marston chronicles the history of Carl Lindström’s Berlin company, under whose Odeon label all these discs were first released. Soon after the electrical system was introduced, Lindström began experimenting with his own version of it, to avoid paying licensing fees in U.S. dollars to Western Electric. The results were uneven, and for reasons given in an intriguing explanation from Christian Zwarg (quoted at some length by Marston), in some instances marked by a deficiency in the low frequency range, producing an overall “tinny” (Marston) or “shrill” (Zwarg) sound. This undoubtedly accounts for an edge we occasionally hear in Lehmann’s timbre that we don’t pick up on her live recordings (for all their own problems) till very late, or on the studio Rosenkavalier and Walküre albums of 1933 and ’35. And as one tracks these restorations for the matrix numbers beginning with “W” (the Western Electric system) or “L” (Lindström’s), yes, from time to time one picks up the difference, which, to his confessed frustration, Marston was able to only somewhat mitigate.

But these distinctions are relative, and to anyone familiar with even the well-curated previous LP and CD transfers—or for that matter with garden-variety 78-rpm pressings—there can be only gratitude for the quality of sound heard throughout this presentation. As Lehmann’s voice jumps eagerly out at us at the start of “Dich, teure Halle,” or insinuates itself into our senses with Strauss’s Morgen!, we are aware of a kind of person-to-person emotional transfer that was uncommon enough in its time, and almost outside our experience now. Some of the difference, certainly, lies in time-and-place cultural attitude. We all have more immediate access to the expressive gestures we encounter from day to day, which also mark the path of least resistance to broad sociocultural inclusion. So when Lehmann summons, as she repeatedly does, what we hear as colors and inflections that sound utterly spontaneous, the outcomes of “natural” responses to music and text that are more directly communicative than most singers’, this cultural comfort and ease explain much.

Not all, though. The particular feminine sensibility we hear in Lehmann was part of many singers’ “style,” but hers still stands out as the most open, complete, and persuasive expression of it. If you were to take some time to compare Lehmann’s singing of (for instance) the two arias each from Tannhäuser and Lohengrin; or of a great song that became popular, like Schubert’s Ave Maria; or of a nicely set once-popular bit of sentiment, like Hildach’s Der Spielmann, with the renditions of Elisabeth Rethberg (and I can assure you you’d have a fine old time doing so), you would notice these things: in Rethberg, we have another certifiably wonderful soprano of the same generation (six years younger) and cultural environment, recording in these same years on the acoustical/electrical cusp. In certain respects, Rethberg can be rated the superior singer—for purity of timbre; clarity of vowels (especially of the open “a”; unforced, simple emission; evenness of scale; and directness of movement over intervals without disruption to the line, she has had very few equals, and though we can hardly say that Lehmann was deficient in these areas (and we must record that Lehmann’s prime was more extended than Rethberg’s), we would probably rate Rethberg slightly higher more times than not. Where Rethberg is decidedly better (though we don’t hear it much on the selections I’ve cited) is in the matter of sustainment on the breath, which is always connected to “support,” and we note that Rethberg had the combination of vocal size and technique (particularly in control of dynamics in the upper range) that enabled her to successfully take on the Verdi spinto and dramatic parts (in Aida, Ballo, Trovatore, Forza, Simon Boccanegra), into which Lehmann did not venture. (Her only Verdi role, in fact, was Desdemona, with which she triumphed over a number of seasons at Covent Garden.)