Das Rheingold is the outlier among the Ring operas, an ensemble work with a fast-shifting plot, animated dialogue, fewer set pieces and less character development. For those reasons, it may be the hardest to pull off convincingly in a concert performance.

A pair of unstaged accounts conducted by Simon Rattle and Jaap van Zweden earlier this year each have a feeling of discovery, featuring orchestras that don’t often perform this music.  

Rattle and the Bavarian Radio Symphony Orchestra serve up the action on a series of emotional swells vividly captured on BR Klassik while van Zweden and the Hong Kong Philharmonic deliver a more deliberate, idiosyncratic account on Naxos, launching the first Ring project by a Hong Kong or mainland Chinese ensemble. If neither ranks among the very best on record, they in different ways force you to reconsider Wagner’s somewhat underrated Vorabend.

Occasionally knocked for his work in the core Romantic repertory, Rattle has tried to build a reputation as a Wagner conductor, leading Ring cycles at Aix, Deutsche Oper Berlin and the Vienna State Opera. The rich, almost symphonic reading here is light years from his 2004 period instrument version and elevated by strong performances from Tomasz Konieczny and Michael Volle. The BRSO makes an excellent partner, with bright-sounding strings, woodwinds that spin out lovely inner details during the quieter passages and a brass section that’s positively spellbinding during the descent into the Nibelheim.

What’s lacking is the instinctive quality you’d find in a staged performance. The back-and-forth between Wotan, Loge and Alberich is a bit stiff, the giants’ interactions could use more suspense and some critical moments such as Erda’s appearance drift by without enough significance. There’s also a certain forced grandeur in the Valhalla music that sounds calculated, though always played with conviction. Rattle’s habit of speeding and slowing the tempi through the two hour, 23 minute performance doesn’t reach the point of micromanagement but has a way of sapping momentum in sections of the final scene and detracting from a truly complete view of the work.

Konieczny, a fine singing actor whose won critical praise as both Wotan and Alberich, is a nuanced but convincing villain here, using his dark, round bass baritone to convey the dwarf’s anguish and make the character more than simply a curse-spitting slave-driver. There’s a subtle charisma as he pries the secret of the gold from the Rhinemaidens and palpable desperation once he’s relieved of the all-powerful ring. Powering through numbers such as “Hieher! Dorthin!” one gets the sense he could own the role for years.

Volle, who’s set to be the Met’s next Wotan, has a commanding sound with a wide vibrato and strong sense of the melodic line. Though the bass-like shadings present an authoritative mien, he leaves the impression of being an impulsive character who’s punching above his weight, with shaky business relations and questionable scruples.

Burkhard Ulrich could lend more to the proceedings with Loge’s unnerving comments and sounds vocally taxed by the final scene. To his credit, he does seem to approach the role as more of a shifty hired gun than the smartest guy on the stage. Peter Rose is a pleasingly lyric if somewhat underpowered Fasolt, contrasting with Eric Halfvarson’s wicked Fafner. The male cast is rounded out by Christian Van Horn as Donner and Herwig Pecoraro as Mime.

Among the women, Janina Baeschle is a otherworldly Erda, unleashing some ominous bottom notes while ably handling Rattle’s spacious pacing. Elisabeth Kulman is a high-handed and suitably imposing Fricka while Annette Dasch provides luxury casting as a sultry Freia. The well-matched trio of Rhine daughters are soprano Mirella Hagen and mezzos Stefanie Iranyi and Eva Vogel.

The set’s biggest selling point may be the excellent engineering, which clearly captures the primordial E-flat rumblings of the double basses in the prelude, a few momentary intonation issues in the lower brass and later, pins one’s ears back with the choir of Nibelungs’ anvils. With no further installments apparently planned, it’s an intriguing one-off that leaves a listener wondering how the same forces would tackle the complexities of Siegfried or Götterdämmerung.

Running ten minutes longer than the Rattle, van Zweden’s Rheingold is drawn from concert performances from the Hong Kong Cultural Center featuring an almost all-Western cast. The orchestral playing is less virtuosic but highly competent, with an emphasis on smooth lines and chamber-like textures. The Dutch maestro is hardly the first conductor to put tonal beauty over high drama and gets admirable buy-in from his band. Unfortunately, he holds back too much power until the very end, rendering moments like Alberich’s curse somewhat wan.

The big attraction here is Matthias Goerne singing his first Wotan with a virile, rich sound in the lower range that may remind some of George London. A bit tentative in the opening scenes, his characterization builds, culminating in a lied-like ode to Valhalla filled with lovely dynamic shadings and sensitive phrasing. One senses the interpretation can’t but deepen as the baritone develops a stronger personal identification with the role.

As Fricka, Michelle DeYoung is dramatically intense if not always tonally secure in “Wotan, Gemahl, erwachte!” but has some of the most natural-sounding dialogue with her castmates. Peter Sidhom’s high-energy approach to Alberich is a case of central casting bad guy but plays quite effectively, especially opposite the Mime of David Cangelosi. Kim Begley is a wonderfully scathing Loge while Deborah Humble works through some uneven orchestral tempi to deliver Erda’s warning with a blend of poignancy and authority. Other notable contributions come from Kwangchul Youn as Fasolt and Oleksandr Pushniak as Donner.

It’s too early to tell where van Zweden’s Ring will go, or whether he will add more spontaneity and majesty to what’s clearly a carefully thought through approach. (Goerne and DeYoung return to record Die Walkure in January, joined by Stuart Skelton as Sigmund and Petra Lang as Brunnhilde). As is, this Rheingold has enough merits captured in good, forward sound to rate as a welcome budget addition to the catalogue.