Unlike some conductors who lock onto their career paths as children, Nicholas Kraemer never imagined himself in that role when he was growing up. In fact, he wasn’t even planning a career in music at first. “Marin Alsop said that she wanted to be a conductor from the age of 9, and Simon Rattle knew that he was going to be conductor from the age of 13,” Kraemer said. “I wanted to be a harpsichord player from about the age of 19, and before that, I wanted to be an actor.”

    But the London-based Kraemer did eventually become a conductor, gaining international recognition particularly for his work in repertoire composed in the Baroque era – 1600 to 1750 – and slightly later music by such Classical-era composers as Franz Joseph Haydn. He will put that expertise to work Nov. 20-25, when he returns to the Chicago Symphony Orchestra, leading the ensemble in a program encompassing all six of J.S. Bach’s celebrated Brandenburg Concertos (dated 1721, though probably composed earlier). He will also take the Orchestra Hall podium Nov. 24 for a concert featuring the Civic Orchestra of Chicago, a training ensemble associated with the symphony’s Negaunee Music Institute. The latter program, which will center on Mozart’s Mass in C Minor (featuring the Chicago Chorale), will include Elgar’s concert overture In the South as well.

    Kraemer studied music history and theory at Nottingham University and played violin (“I was a terrible violinist,” he said) and piano on the side.  Then he thought, “I don’t want to be an academic musician at all, actually. I want to play,” he said. So not desiring to be a concert pianist, he turned his attention to becoming a répétiteur, a fancy music-world term for a vocal coach-accompanist. But continuing his studies at the Guildhall School of Music, he fell in love with the harpsichord and the idea of playing continuo, the accompaniment that supplies the bass line and harmonic support in Baroque music. “Being a continuo player is a fantastic skill, and I still think that,” he said. “And I wanted to play with the best groups in the world, and within two to three years of leaving college, I was with the Academy of St. Martin in the Fields.”

    The harpsichordist gradually began directing a few works from the keyboard, and that led to some small-scale conducting engagements. At one such concert, someone asked if he would like to lead the English Chamber Orchestra; he quickly said yes, beginning a series of high-profile engagements with the ensemble that lasted from 1975 through 1983. But Kraemer looks back at that time now with regret, believing he might have squandered the opportunity, because he did not do as well as he wishes he would have. “I didn’t do myself justice with the ECO,” he said. “It was too early, too soon for me. I wasn’t that young, but I just wanted everybody to have a good time. And as a result, I really didn’t really push them.”

    Despite such checkered memories, he is nonetheless celebrating his 70th birthday next year by overseeing a special concert with the orchestra.

    What Kraemer calls his “road-to-Damascus moment” came when he studied briefly at the Schola Cantorum in Basel, Switzerland. He attended a concert in Geneva featuring the Leonhardt-Consort, an ensemble led by famed Dutch harpsichordist and conductor Gustav Leonhardt, a pioneer in the period-instrument movement. The crusade, which caught fire in the 1970s with the establishment of such popular groups as the Academy of Ancient Music, advocated a return to performance styles as close as possible to those at the time when 17th- and 18th-century and earlier works were written. That approach meant, among other things, employing original instruments, including violins with gut strings, and striving for a lighter, more transparent sound.

    What Kraemer recalls from that Geneva concert is a “light-sprung” sound, rhythmic textures and forward-moving phrasing. “Bach with a smile,” he said. “It’s affected me ever since.”

    Although the conductor has led other period-instrument ensembles, including the now-disbanded Raglan Baroque Players, which Kraemer formed in 1978, he has specialized in bringing a period sensibility to ensembles that perform on modern instruments. “That’s what I do, and I guess I just got good at it,” he said. “It’s never going to sound the same, but I think I’ve found a way to make it acceptable to myself, and if it’s acceptable to myself, I reckon that other people will like it, too.”

    Kraemer has served as associate conductor of the BBC Scottish Symphony and artistic director of the Irish Chamber Orchestra and London Bach Orchestra. He is currently permanent guest conductor of the Manchester (England) Camerata and principal guest conductor of the Kristiansand (Norway) Symphony Orchestra. In addition, he has guest conducted such orchestras as the Berlin Philharmonic, Rotterdam Philharmonic, Bergen Philharmonic, BBC Philharmonic, Colorado Symphony and Minnesota Orchestra.

    He came to the attention of the Chicago Symphony after his 2002 appointment as principal guest conductor of Music of the Baroque, a Chicago-based chamber ensemble headed by noted conductor Jane Glover. He has led two previous programs with the CSO — one that included Handel’s Water Music and another that included works by Haydn and Telemann as well as Richard Strauss’ Metamorphosen, which was written at the end of World War II. In each case, Kraemer led a chamber-sized ensemble of symphony musicians; that will be the case again with this latest appearance, when leading from the harpsichord for most of the program, he will conduct a group of about 30 players.

    He calls the Brandenburg concertos “the summit of high-Baroque instrumental music” and describes them as standing out from anything else written during that era because of their striking individuality. “You look at the Brandenburgs’ – they’re all different,” he said. “Their colors are all different. They’ve got different orchestrations.” Even when the musical themes are similar, as they are in the opening of the first and second concertos, they still sound completely unalike because of contrasting orchestrations. Bach was consumed with finding distinctive ensemble colors, Kraemer said, and the composer achieved that goal “fantastically” with the concertos that are in the same key. He notes, for example, that the third and fourth concertos are in G major, but they sound “extraordinarily different,” because one is a concerto for strings and the other a concerto for violin and two recorders (performed in this case by flutes).

    To succeed, performances of the concertos have to dance. “You don’t have to make them dance, you let them dance,” he said. Especially in the 1950s and ’60s and sometimes even now, certain musicians have brought a heavy, Germanic quality to these works, a performing style he calls “frowning Bach” or “Bach with heavy boots.” “I just don’t feel it like that,” he said. “So my approach is to keep it off the ground – light rhythms.”

    With the CSO, he will conduct the six works the way he would with the Music of the Baroque or any other ensemble. “Apart from the fact that I know the Music of the Baroque really well,” he said, “and I don’t really know the Chicago Symphony that well, there is no difference of approach, because it is music-led. So I’ll always approach the project from the music rather than from the players.”

    He begins by running through a piece with the musicians and simply listening. “Is this as I would want it?” he said. “Maybe I need to adjust this bit — a bit there, a bit here.”

    To speed the process, the conductor is supplying the CSO with musical parts that have been notated with the bowings and phrasings he wants. “The Music of the Baroque [players] are so used to me that they do what I want before I say anything,” he said. “They know what I’m going to say. But I found with the symphony that they were very, very quick [learners].”

    Whether in Chicago or elsewhere, Kraemer believes he is doing some of the best conducting of his career. He is preparing harder than ever, and he doesn’t worry anymore about what other people think of his interpretations. “Only now – the last five or six years – have I really felt that,” he said. “It’s a revelation, actually. It means that I enjoy what I do much more than I did. I never dread anything anymore.”

    Kyle MacMillan, former classical music critic of the Denver Post, is a Chicago-based arts writer.