Peder Karlsson (Sweden) has worked with the same people for long periods of time. Twenty-six years with The Real Group, six years with Perpetuum Jazzile, and eleven years with the leadership team at RAMA Vocal Center. In 2021, Peder was a part of initiating Choirs for Ecocide Law, an international choral concert project which raises the issue of making large-scale environmental destruction an international crime.
With The Real Group, Peder developed methods for navigating a musical terrain where most things to know are unknown, and where a methodology for exploration is required. Over time, the Real Group singers learned about which skills they needed to develop. Today, Peder gathers his experiences into a learning system – Play It By Voice, which combines clearly defined knowledge for ensemble singers with methods for exploring potential within yourself and within your group.
Rosana Eckert (America) is an internationally acclaimed jazz vocalist, improviser, songwriter, arranger, and educator known for blending virtuosity with warmth and originality. Deeply rooted in jazz yet stylistically adventurous, she has performed and recorded with artists such as Bobby McFerrin, Christian McBride, and New York Voices, and appeared on the Grammy Award winning composition “Eberhard” by Lyle Mays.
A dynamic bandleader and recording artist, she brings expressive storytelling and inventive improvisation to every stage. Rosana is Principal Lecturer of Jazz Voice at the University of North Texas, where she has helped shape one of the world’s leading vocal jazz programs while inspiring singers across generations.
Julian Knörzer (Germany) studied school music and choral conducting (MH-Freiburg, RAMA Vocal Center). He is active in the German vocal scene as a choir director, beatboxer, singer, and arranger (Jazzchor Freiburg, Twäng!, UNDUZO, Acoustic Instinct) and works internationally as a lecturer. In the field of beatboxing, he specializes in accompanying vocal ensembles, which led him to publish the book “Beatbox Your Choir – Chöre und Vocal Groups perfekt begleiten” (Schott) in 2015. Julian Knörzer teaches jazz/pop choir conducting and beatboxing at the Freiburg University of Music and the Tübingen University of Church Music. In addition to his teaching activities and active concert life, he co-founded the Black Forest Voices vocal music festival in 2019.
Stefan Rheidt (Germany) holds a degree from the SWISS JAZZ SCHOOL in Bern (CH) and the COMPLETE VOCAL INSTITUTE in Copenhagen (DK). In addition to his work as a vocal coach, he also works as a choir director and arranger. His most important projects are his vocal academy Vocalive, his choir (jazzchor-vocalise.de), and his ukulele trio Ukulala.
Maggie Horrer (Germany) studied jazz vocals in Freiburg and Lucerne (Switzerland), graduating in 2017 with a Master of Arts in Music/ Jazz vocals and Music Education. She has been teaching voice since 2006 and currently instructs aspiring educators at the Merian-Schule in Freiburg, as well as leading workshops for the ”Singen mit Kindern“ Foundation. As a singer, Maggie performs with the Jazzchor Freiburg, among others. To Kids, however, her warm voice is most familiar through her recordings for the ”Lauschelieder“ albums.
Nina Ruckhaber (Germany) is co-founder and organisational director of the Black Forest Voices a cappella festival. She has been singing in the Freiburg Jazz Choir for over 15 years and is media director of the German Youth Choral Association. She works with numerous vocal festivals and vocal bands, including vokal.total Graz, MAYBEBOP, ONAIR and New York Voices, and has an extensive network in the popular choir and a cappella scene. With Ninas VoxBox, she has also established her own online platform dedicated to vocal music.
Ingo Rau (Germany) studied Psychology at the University of Freiburg and Tonmeister in Detmold before founding AMPS Factory Studios, specializing in audiophile analogue recording. A full time producer and sound engineer since 1994, he was mentored at the Experimentalstudio der Heinrich-Strobel-Stiftung des Südwestfunks Freiburg, where the groundbreaking Halaphon system, developed with Peter Lawo and used in works by Karlheinz Stockhausen, shaped his approach to spatial sound. Since 2002, he has focused on immersive surround concepts for live concerts, touring internationally with innovative, high fidelity productions.
Bam Rodríguez (Venezuela) is a Venezuelan born, New York based bassist whose artistry moves fluidly across classical, jazz, Latin, and global traditions. A member of Afro Latin Jazz Orchestra led by Arturo O'Farrill, he won the 2022 Grammy Award for Best Latin Jazz Album for Fandango at the Wall in New York. He has shared stages with legends including Chucho Valdés, Wynton Marsalis, and Joe Lovano, performing at venues such as Carnegie Hall, North Sea Jazz Festival, and Taiwan’s National Theater and Concert Hall. In 2024, he returned as a featured artist at the National Theater and Concert Hall Jazz Festival. Beyond performance, he leads projects like South by North East and founded We Are Starting a School, expanding access to music education worldwide.
Gabriel Hahn (Germany) is a German drummer with a Master’s degree in Composition and Arranging from the Munich and Dresden Universities of Music. Active in body percussion and vocal percussion, he has performed alongside many renowned German artists.
Since 2009, he has toured internationally as drummer and vocal percussionist with the world acclaimed jazz ensemble The New York Voices, contributing to the album Reminiscing in Tempo. In 2017, he joined Brussels Vocal Project as a featured vocalist on the production Modern Tales. Continuously exploring new forms of musical expression, Gabriel has trained in Indian, Arabic, and Latin American percussion traditions and regularly leads workshops across Europe, Asia, and the United States. Based in Berlin, he founded Body Music Berlin and established the community initiative “Music + Human Body,” promoting accessible artistic exchange and inspiring wider audiences to discover the expressive power of body music.
Christine Liu (Taiwan) is a leading Taiwanese a cappella musician and church organist whose work spans composition, arranging, performance, teaching, and liturgical accompaniment. Trained in piano from childhood, she was active in school and church choirs and first gained recognition by winning a national composition competition in junior high school. While studying in the United States, she became involved in contemporary a cappella, later majoring in composition at Northwestern University, where she founded the first Chinese student a cappella group, The Treblemakers. Since 2004, her award winning a cappella arrangements have been widely performed.
After graduation, she pursued church music studies in Vienna before returning to Taiwan to found Voco Novo in 2009, blending traditional culture and Indigenous music with contemporary a cappella. She currently serves as alto and Music Director of Voco Novo, Artistic Director of the Vocal Asia Festival, principal organist of Holy Family Church, and conductor of the Tabor Youth Group.