Just who does set the bench mark?

WHEN Ian Bostridge, the English tenor, and Leif Ove Andsnes, the Norwegian pianist, take the stage at Walt Disney Concert Hall on Wednesday, they will be furthering a great tradition -- and a great debate.

Their program will feature lieder by Schubert and Beethoven, with the pianist accompanying the tenor. And the word “accompanist” stands at the center of this controversy: A successful lieder performance requires a delicate balance, and what sort of pianist best serves the art form remains in dispute.

“Playing for a singer requires a lot of self-abnegation,” Bostridge said recently from his home in London. “The voice is a fragile instrument, and you have to think about accommodating it.”

Andsnes, speaking from Norway, echoed those sentiments.

“When you work with an instrument, you don’t have the danger of getting exhausted,” he said. “Voices have to be nurtured -- you can’t just go on for hours and hours.”

That helps explain why there’s a branch of pianism devoted to accompaniment. Its self-effacing practitioners, often scholars and coaches as well as players, are particularly attuned to the needs of singers. (Not for nothing did Gerald Moore, the 20th century’s most famous accompanist, title one of his memoirs “Am I Too Loud?”)

But these players are rarely known outside music circles. Instead, pianists such as Andsnes, Alfred Brendel, Andras Schiff and Vladimir Ashkenazy, who made their names as soloists, help fire the public’s interest in lieder, often dramatically increasing the star power of a singer-pianist pairing.

Naturally, being elbowed aside by more celebrated musicians doesn’t thrill professional accompanists. Graham Johnson -- who, like Andsnes, has performed and recorded with Bostridge and who was something of a mentor to him -- is arguably the most esteemed such pianist today, and a noted authority on art song.

“If a solo pianist can do my job simply by opening up the score and playing the music better than me without thinking, then why should people take the trouble to study accompanying?” the London-based Johnson said via e-mail. “Someone once had the gall to ask me to give a few tips to a solo pianist over the phone, as if this were all it would take to get the guy on the right track.”

Andsnes doesn’t disagree about preparation. “Of course, you have to study the repertoire,” he said. “But that’s true with everything. If you devote your life to Beethoven, you are better at that than at playing Tchaikovsky.”

He takes exception, though, to the notion that only professional accompanists should partner singers. “To be honest, I’ve never understood the distinction between accompanist and soloist,” he said. “I’m just a musician. And I’ve always found that you get the best result in lieder when you have a real pianist at the piano. Of course, it’s good to look at the text, but apart from that, it’s much the same as making chamber music with any other instrument.”

That term, “real pianist,” cuts to the heart of the matter and is a phrase Johnson as good as anticipated.

“I get upset about this issue,” he wrote, “because it insultingly supposes that the art to which I have given my life is something anyone who is a good pianist can do. No, the implication is it can be done better by a soloist, because virtuosity governs all. And from there, it’s a short distance to consider an accompanist a pianistic butler, a loser who plays cringingly for tyrannical soloists in the hope of another crumb from the table.”

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High-profile collaborators

THE pairing of lieder singers with more renowned musical figures is nothing new. Go back to the art form’s roots as a public affair and you’ll find the revered Elena Gerhardt getting her start at 20 accompanied by Arthur Nikisch, then music director of the Berlin Philharmonic and the Leipzig Gewandhaus Orchestra.

In fact, several of the last century’s most acclaimed lieder singers formed nonexclusive partnerships with famous musicians, including English contralto Kathleen Ferrier (with conductor Bruno Walter as pianist) and German soprano Elisabeth Schwarzkopf (with Edwin Fischer, Walter Gieseking and, less successfully, Glenn Gould). But no one did more to focus the spotlight on the keyboard than Dietrich Fischer-Dieskau, the German baritone whose name is virtually synonymous with lieder singing and who in a 40-odd-year career ending in 1992 worked with players as diverse as Brendel, Daniel Barenboim, Christoph Eschenbach, Sviatoslav Richter and Leonard Bernstein.

Speaking from his London home, Brendel, who has also played for baritones Hermann Prey and, more recently, Matthias Goerne, credited Fischer-Dieskau with recasting the role of accompanist from lackey to collaborator.

“The unequal partner is something of the past thanks to Fischer-Dieskau,” he said. “Onstage with Fischer-Dieskau, there was the ideal give and take. You knew that he listened to you as much as you listened to him.”

Yet singers face significant challenges working with pianists as famous, or more famous, than themselves. For American soprano Barbara Bonney, the issue is control. “It can be very exciting to have the stimulus of a huge personality at the piano,” she said. “But it can also be a bit of a tug of war when it comes to interpretation.”

And booking two popular artists is twice as hard as booking one. “It’s never easy to find dates with these people,” said Bostridge, referring not just to Andsnes but also to his other “star” piano partners: Mitsuko Uchida, conductor Antonio Pappano and composer Thomas Ades. “You have to plan a long, long time in advance.”

Moreover, even solo pianists especially committed to lieder can indulge in this passion only so long. “What you have to realize when working with soloists,” said Bostridge, “is that however much they love song, their priorities lie elsewhere.”

Indeed, the well-received series of Schubert songs that Bostridge and Andsnes have recorded since 2001 is scheduled to conclude this year. Then Andsnes plans to turn his attention to Beethoven’s piano music.

Perhaps that’s why Bostridge, presumably like many other singers, feels a certain loyalty to his longtime accompanist, Julius Drake, who will play 40 of the tenor’s 49 recital dates this season.

“Everything else is a bit adulterous, really,” said Bostridge. “Julius is used to me, and I’m used to Julius. That has advantages.”

Asserting the benefits of both approaches, the tenor opts to celebrate diversity.

“Gerald Moore couldn’t play the piano as virtuosically as many colleagues, but there’s something extraordinary about what he could do,” he said. “They are different musical experiences, but one doesn’t want to rank them. The important thing is that the music comes out fresh each time.”

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Ian Bostridge/Leif Ove Andsnes

Where: Walt Disney Concert Hall, 111 S. Grand Ave., L.A.

When: 8 p.m. Wednesday

Price: $15 to $82

Contact: (323) 850-2000 or www.laphil.com