Even under new management, the American Repertory Theatre remains loyal to minimalist composer Philip Glass. The Sound of a Voice, two one-act, two-character music-theater settings of early plays by David Henry (M. Butterfly) Hwang, is the latest in a series of ART Glass commissions that have included The Juniper Tree (1985), The Fall of the House of Usher (1988), and Orphée (1993, based on Jean Cocteau’s surrealistic cinematic masterpiece). This devotion is noble. But these aren’t among Glass’s best work, and The Sound of a Voice makes for a mostly tiresome and unsatisfying evening of music or theater.

" They were very linear, but they had abstract qualities I liked, " Glass says about Hwang’s plays, The Sound of a Voice and Hotel of Dreams, which date from the early 1980s. " At first I wanted to make them into two one-act operas, but I decided to do something different — a real combination of theater and opera. I was interested in the interaction of characters and the impact of what characters say to one another. In opera, the voice often becomes a spectacle in sound, but in theater, you have interaction. I tried to make the voices as conversational as possible, but still have them singing ... there aren’t even any duets. "

In other words, Glass has made two operas that consist almost entirely of recitatives, the " parlando " (sung " speaking " ) parts of operas that audiences put up with while they’re waiting for the memorable arias and duets. His best works — Einstein on the Beach, Akhnaten, Satyagraha — have so few " linear " qualities (plot, narrative, dramatic interaction), maybe he’s forgotten that traditional opera is theater, that it has always been " interested in the interaction of characters and the impact of what characters say to one another. " Hasn’t Glass ever seen La traviata, with its inspired " conversations, " La bohème, or Carmen? The Sound of a Voice isn’t " something different " ; it cops out because it doesn’t try to do what opera does best — use the sound of a voice to express and reveal powerful emotion.

Any composer would have a hard time setting these talky and undramatic plays. The Sound of a Voice was suggested by Japanese ghost stories about a woman in the woods who might really be a ghost or a witch (think of Keats’s " La Belle Dame Sans Merci " or the Beatles’ " Norwegian Wood " ). A samurai warrior comes to the woman’s crooked house in the woods (designer Robert Israel’s tilted rice-paper cube, which we can sometimes see through). He is captivated by her — stays, chops her wood, spies on her. It ends in either murder or suicide. Hotel of Dreams is about an aging writer who visits something like a geisha house (the tilted cube becomes the stairway to the upper rooms). He doesn’t want to be like other old men, horny, impotent, desperate to encounter naked pretty girls; yet he keeps coming back. The experience frees him from his writer’s block. Or is the madam of the brothel an image of a lost love? The piece ends in a double suicide. Since there’s no suspense, I don’t feel guilty about giving away the endings.

Hwang’s dialogue is filled with portentous platitudes: " Now when I’m awake I can only remember what it’s like to remember " ; " People kill themselves to save themselves, not others " ; " At our age, starting again is worthwhile only if one enjoys the process " ; " Time begins with the entrance of a visitor and ends with his exit " ; " Voice is the simplest thing to find and the hardest thing to hold onto. " ( " Not unmeaningless, " as a friend of mine is fond of saying.) These pseudo-profundities alternate with ludicrously flat colloquialisms ( " You were great — we were a team " ), sometimes in rapid succession:

" They say age brings wisdom. "

" That’s a laugh. "

At least four times a character repeats some version of " Don’t be ridiculous " — a phrase that sounds even sillier when it’s sung. Countless sentences are interrupted by melodramatic ellipses: " I wanted to hit her, but instead — " dot-dot-dot. Hwang reaches for philosophical depth, but achieves little more than affectation. He was in his early 20s when he wrote these plays. For all their clumsiness, it’s easier to discern their youthful promise than to see why a mature composer would want to work with them.

The places where Glass’s music comes most to life are in the unspoken interludes between scenes. The " orchestra " is a small chamber quartet, conducted by Alan Johnson. Multiple percussion instruments (wood blocks, tom-toms, tam-tams, wind chimes, finger cymbals, castanets, glockenspiel, and various Near or Far Eastern drums) are played dexterously by Robert Schulz. Rebecca Patterson’s cello creates the underlying harmony. Susan Gall on flute, piccolo, and " shakuhachi " — the witch’s bamboo flute with its haunting " bent " notes — is especially effective in the interlude during which the samurai is spying on the woman. At the center is the pipa — a Chinese stringed instrument that can sound like a lute, a guitar, a mandolin, a sitar, or even a harpsichord. This is played, rivetingly, by Wu Man, the Yo-Yo Ma of the pipa, and her long, intense solos — sometimes folk-like, sometimes minimalist, sometimes an unexpected mixture — are the most dramatic moments in the entire performance.

Glass was obviously going for exoticism. But too often the music sounds as if it were intended for The Twilight Zone — or, at its thinnest, for The $64,000 Question (quiz-show anticipation music). In traditional opera, flowery language lends itself to soaring music. But Glass’s music neither soars nor illuminates conversational inflections. His word settings seem awkward, arbitrary, unidiomatic, and poorly paced — sometimes too slow, often too rushed. Hwang’s flatness might work better if it didn’t have to be sung; Glass’s music might be more effective as atmosphere, without a vocal line.

The production itself is hardly more than adequate. Robert Woodruff’s stiff blocking more often than not reflects the static and unfocused qualities of the musical and verbal languages. He tries to keep the performers in motion as much as he can, but that isn’t always possible. It’s a little strange to see the man in Hotel of Dreams sitting at the edge of the stage with his legs dangling into the orchestra pit, but I suppose it’s better than having him just stand around. The sets are spare and symbolic. The cube in the middle of Hotel of Dreams makes it hard to see some of the stage business.

One surprising choice in this project is not using any Asian or Asian-American singers for these Japanese characters. Both women singers are Caucasian, both men African-American — and none of them make themselves up to be Japanese (though a key gesture in Hotel of Dreams is the madam powdering her face white). This may have been a deliberate effort to universalize the implications of these plays, the way the music hints at but doesn’t reproduce authentic Orientalism.

The singers are all excellent. Baritone Eugene Perry and bass-baritone Herbert Perry are identical twins who are probably best known as Don Giovanni and his servant Leporello on the PBS telecast of Peter Sellars’s provocative production of Mozart’s Don Giovanni — the one set in the South Bronx (I’ve never been more convinced that the other characters in the opera could be deluded when these two characters trade places). Herbert plays the curious samurai, Eugene the obsessed writer. Eugene has the more compelling role and poignantly conveys not only the writer’s pathetic reluctance to give himself over to the brothel but also his self-deception. It’s a very skillful and subtle acting job, though the performer’s voice the night I went was often rough and strained. Herbert’s role is more one-note, but his on-stage ease and resonant singing are high points.

The women are soprano Suzan Hanson, as the mysterious witch, and mezzo-soprano Janice Felty, as the madam. Hanson, who also appeared at ART in Glass’s The Fall of the House of Usher, has a strong and attractive, but somewhat anonymous, voice. Her English diction, however, is a bit muddy, and it was during her singing that I found myself turning most often to the projected supertitles. She’s supposed to be something of a blank, and I don’t mean it as a putdown to say that this is just what she succeeds in suggesting.

Felty is one of America’s most versatile and commanding singing actresses, and another Peter Sellars Mozart alum (in PBS’s Così fan tutte, she was a more richly fleshed-out Dorabella than most — not the usual simpering ninny). You can see an excellent example of her power on the Houston Grand Opera DVD of Kurt Weill’s Street Scene. The madam may be the most seriously underwritten part in these plays. But Felty’s strong voice and powerful concentration make it impossible to ignore her. Hotel of Dreams isn’t any better than The Sound of a Voice, but because Felty and Eugene Perry have more opportunity for dramatic " interaction, " it is the easier of the two pieces to stay awake through.