Three new Eloquence boxes have appeared, each celebrating a lesser-known conductor from the late 20th century, and each containing some first-rate performances and unusual works.

The truly obscure name is the German musician, Otto Gerdes (1920–1989). When these recordings were made in the early 1960s, his primary job was as Herbert von Karajan’s recording producer. Gerdes produced Karajan’s iconic first set of Beethoven symphonies for DG, and many others. However, when he referred to Karajan as his “colleague” (meaning fellow conductor), the narcissistic Karajan had him sacked.

That was the end, more or less, of both of Gerdes’s careers. His conducting style was in sharp contrast to Karajan’s. Gerdes was concerned with clarity and balance above all: rhythms are pointed, and his woodwinds are prominent. Karajan was old school: his recordings featured string-drenched textures and soft-edged polish, even more so after Gerdes left.

These discs include obscure works that Karajan probably did not want to record, but that is why they are valuable. An excellent program of Hugo Wolf includes the romantic tone poem Pentheselia, rarely if ever played, and the Italian Serenade. That lovely piece gets an easy-going, relaxed performance, not as...