In 2006, Maestro successfully completed his tenure as Artistic Director/ Principal Conductor of Daejeon Philharmonic Orchestra in Korea with which he toured North America in 2004 and Japan in 2005. The DPO and Hahm performed with remarkable responses from the audience and critics alike. Their successful debut in leading concert halls including Carnegie Hall (New York), Kimmel Center (Philadelphia), Benaroya Hall (Seattle), Meyerhoff Symphony Hall (Baltimore), Tokyo Opera City Concert Hall and Osaka Symphony Hall created a new chapter of its twenty years of history. The orchestra thoroughly benefited from his artistic leadership by selling out all concerts.

He had served as Music Director of the Abilene Philharmonic Orchestra for a decade (1993–2003). During his tenure he successfully accomplished community orchestras to true professional regional orchestras. He was profiled on ABC's World News Tonight for his central role in rejuvenating and revitalizing the community.

Maestro Hahm is equally talented and enthusiastic as well as inspirational to young musicians. Currently, he serves as music director of Philharmonia Orchestra of Yale and teaches graduate orchestral conducting programs at Yale University. He was the music director of Yale Symphony Orchestra for nine years (1995–2004). While pursuing his conducting studies at the Eastman School of Music in Rochester, New York, he founded the Gibbs Orchestra. His total musicianship with entrepreneur talents led it to grow from a chamber ensemble to a full-sized professional orchestra within four years. All Gibbs Orchestra’s concerts were broadcast by public radio station WXXI.

As a popular guest conductor, he has conducted the orchestras of Atlanta, Los Angeles, St. Petersburg, Geneva, Besancon, Warsaw, Prague, Bilbao, New York, Bangkok, Fort Worth, Louisville, Toronto, Omaha, Hartford, Alabama, Lincoln, Erie, Memphis, Boulder, Colorado Springs, and the countries of France, Switzerland, Hungary, Austria, Spain, Japan, and Mexico. The Korean National Radio and Television Symphony Orchestra have annually engaged maestro since 1992. He directed its 1995 North America tour in celebration of the fiftieth anniversary of Korean independence. He is also an active opera conductor and has performed numerous spectaculars with Silesian National Opera in Poland.

As a champion of new music, he attracts living composers’ ambitious premiere works. His innovative programming was particularly noticeable. Hahm is one of few avid conductors who commissions new compositions in numerous occasions. Maestro has completed or underway of cycle of Mahler, Stravinsky, Debussy, Berlioz, Brahms, R. Strauss, Beethoven’s complete symphonic works and major choral-orchestral compositions.

Maestro Hahm has received variety of honors and awards, including the Fourth Gregor Fitelberg International Competition for Conductors, the Walter Hagen Conducting Prize from the Eastman School of Music and the Shepherd Society Award from Rice University. In 1997, he was one of a select group of conductors to appear at the American Symphony Orchestra League's National Conductor Preview. In 1995 Maestro Hahm was decorated by the Korean Government with the Arts & Culture Medal at a ceremony in honor of the fiftieth anniversary of Korean independence.

He has studied conducting at Rice University and Eastman School of Music. He lives in Connecticut and enjoys gardening, cooking and playing soccer.