The transpartisan powerhouse duo has attracted national media attention - and controversy. Human-rights activists are talking of protesting because of Rice's involvement in approving the government's interrogation techniques.
For now, the Philadelphia concert, a benefit for the Mann's educational programs, is their sole planned outing.
"Let's see what we think after this one is over," said Franklin, who hatched the idea after discovering, in essence, that Rice was as intimate with Brahms' Piano Quintet in F minor as she was with "Uncertain Allegiance: The Soviet Union and the Czechoslovak Army, 1948-1983" (her dissertation).
"I was reading some article, and I read that Ms. Rice was a classical pianist, and I said, 'A classical pianist?' " recalled Franklin. "That was a stretch from what we all knew about her, so I had my secretary pick up some of her recordings, and I did like what I heard. So I said, 'I sing arias, she plays classical,' and we could raise money for something. There are people in such dire need today, so many people. We need to raise some money and contribute to our favorite and most needy charities."
Rice didn't need convincing.
"I couldn't pass up an opportunity to perform with the Queen of Soul. I've been a huge fan for all of my life," said Rice, who has returned to Stanford University as a professor of business and political science after an eight-year leave to serve as President George W. Bush's national security adviser and then secretary of state. "We first met at a White House dinner and started talking, and one thing led to another."
The idea was handed to Princeton Entertainment, a tour producer with big-name acts such as Andrea Bocelli, Cher, and the Irish Tenors, which took the idea to the Mann.
Rice and Franklin, both daughters of clergymen, share no political ideology: Franklin is a self-described "staunch" Democrat who provided a memorable soundtrack to President Obama's inauguration, Rice a highly visible personification of the Bush 43 era.
They haven't talked politics.
"Definitely not. Just don't," said Franklin, whose last major performance here was in 2007 at the Dell East in Fairmount Park. "Our motivation here is to raise money. This is a bipartisan effort for all of our people."
Some have been less inclined to turn a blind eye to Rice's nonmusical resumé. Sebastian Doggart, a human-rights activist in New York and documentarian of American Faust: From Condi to Neo-Condi, argues that Rice was a principal player in the Bush interrogation program, and has urged the Philadelphia Orchestra to not perform with her.
Rice and other senior Bush officials reviewed and approved CIA use of harsh interrogation techniques, including waterboarding, on detainees at secret prisons, according to a Senate Intelligence Committee report declassified in 2009.
Doggart called the concert an attempt at a "restoration" of Rice's image.
Steven Jewell, a Stanford alumnus, has organized a petition asking the university to investigate "whether to be involved in a torture program on leave from the university is compatible with her duties as a university professor."
"Torture is a crime against humanity, and to have her treated by a cultural organization as if she is just simply an artist, without the context of her involvement in crimes against humanity, is reprehensible," he said.
Rice declined to respond.
"I have no comment on the 'activists,' " she wrote in an e-mail. "This is, of course, a concert to benefit kids - nothing else."
Rice spokesman Colby Cooper said she was not taking a fee for the concert, which might be repeated elsewhere if it "has truly been a success for the Mann Center and Philadelphia."
Jewell said he had written to more than a half-dozen Philadelphia Orchestra officials, including Rossen Milanov (one of three conductors for the concert), asking that Rice be banned from the event.
"It would be a grave mistake to tarnish your own reputation and that of the orchestra with this event," he wrote.
Jewell said he had received no response.
An orchestra spokeswoman said president Allison B. Vulgamore was on vacation and would have no comment on the concert.
Mann president Catherine M. Cahill offered only the most opaque acknowledgment of controversy - even declining to say whether she has heard from anyone who wants to see the Mann drop Rice from the concert.
"For folks who are not interested in coming, they certainly have their points of view," she said.
She said that Franklin, too, was taking no fee for the concert, and that proceeds would go to support programs in schools and to concerts and workshops for children. As of Friday, only a few hundred of the Mann's approximately 4,500 under-cover seats remained unsold, a Mann spokeswoman said.
Rice, 55, may surprise some with this pianistic foray, but she has played piano since she was 3 - her name is derived from con dolcezza, Italian for "with sweetness," she said - and even during her D.C. years she managed to practice and keep up chamber-music partnerships.
She once harbored hopes of becoming a professional pianist - she studied at the University of Denver - but after hearing other students at the Aspen Music Festival, she changed course and eventually arrived at a relationship with music as ardent amateur.
"I think I am always evolving," she said. "As a music major as a teenager, I was technically better than I will ever be again. I was practicing four hours a day, and I was pretty good. But I've recently played the Schubert Fantasy for Four Hands, and for the first time I felt so emotionally connected I had to say to myself, 'Stay with it. You have to continue to play.' That's an experience I had never had. When I'm working at it, it puts me emotionally at a very different place than anything else."
Though experienced in the chamber-music realm, she has played with an orchestra only once - the Denver Symphony in this same Mozart concerto - and never with a major orchestra.
That Denver performance was four decades ago (she was 15), but she remembers being suddenly engulfed by all that sound, and found it jarring.
"It's going to be an interesting experience. I'm trying to get prepared for that moment when I first hear them. With the Denver Symphony, I remember being stunned at the bigness of it, and I'm trying to channel that experience."
Equanimity shouldn't be a problem for the diplomat nicknamed "Warrior Princess." Rice has often played before high-tone company - Supreme Court justices, Alan Greenspan, and, at one concert, Queen Elizabeth II.
"She was lovely," said Rice. But, she added, "she wasn't a music critic."
Franklin said she had been similarly connected to classical at a certain level since she was a child.
"As I got older and more mature, the more I would listen to our classical station. I love listening to classical when I am off. After concerts, it's a wonderful mode of relaxation. I love the melodies. That's kind of how I got into it."
And at 68, she's moving further into the genre.
"I am going to record a classical CD before the year is out," she said. "There will be a number of things on it. 'O mio babbino caro.' 'Nessun dorma.' " Both are on the Mann program.
"Usually when I hear a melodic piece on the classical station that I like, eight times out of 10 it's Puccini. I love Chopin as well. Brahms is a little too down for me. The mood is too down. Although I am sure there are other pieces by him that are more up than the ones I heard. I just didn't care for what I heard."
Rice, for the record, is a Brahms partisan. "Johannes Brahms is by far my favorite composer," she told the University of Denver magazine this year. "It is in part because he was a great classicist, but he was also pushing music toward the 20th century."
So the world won't get to hear Franklin in Brahms songs. Her planned CD will pair her with an orchestra, though she's not yet sure which one.
"I am going to pick a symphony. I was thinking of the New York Philharmonic or the Chicago Symphony, just because I've done things with the Detroit Symphony and I like to spread it around."
Ahem. Why not a certain orchestra she'll perform with Tuesday night?
"I have not heard the Philadelphia symphony," she said. "I'll make it my business, and perhaps it could turn out to be them."
If You Go
Aretha Franklin and Condoleezza Rice will perform with the Philadelphia Orchestra, led by Rossen Milanov, Thomas Wilkins, and H.B. Barnum, at 8 p.m. Tuesday at the Mann Center for the Performing Arts in Fairmount Park. Tickets are $24 to $95. For more information, call 215-893-1999 or visit www.manncenter.org
Contact music critic Peter Dobrin
at 215-854-5611 or email@example.com. Read his blog at www.philly.com/philly/blogs/artswatch/