Sergey Ostrovsky is a solo violinist, conductor, founder and first violin of the Aviv String Quartet for 27 seasons, founder and Artistic Director of the ‘Ensemble Symphonique de Genève’ and has taught violin at the Haute Ecole de Musique de Genève and Neuchâtel since 2009. He was First Solo Violin of the ‘Orchestre de la Suisse Romande’ from 2007 to 2012. He was also First Solo Violin of the ‘Orquesta de la Communidad Valenciana’ from 2012 to 2015.

Sergey Ostrovsky won the Grand Prize at the 3rd Melbourne International Chamber Music Competition. He is a laureate of the Bordeaux International String Quartet Competition, 2nd Prize winner of the ‘Schubert and Modernity’ International Competition in Graz (Schubert Prize), as well as a laureate of the ‘Prague Spring’ International Competition and the Rodolfo Lipitzer Prize.

As a soloist, Sergey Ostrovsky plays with prestigious orchestras such as the ‘Orchestre de la Suisse Romande’, the Israel Philharmonic Orchestra, the Geneva Chamber Orchestra, the Cape Town Philharmonic Orchestra, the Amadeus Chamber Orchestra (Poland), the Bournemouth Symphony Orchestra, the ‘Orquesta de la Communidad Valenciana’, the Jerusalem Symphony Orchestra, the ‘Luzerner Sinfonieorchester’ and the Israel Chamber Orchestra.

A passionate conductor, Sergey Ostrovsky is regularly invited to conduct in Switzerland, Spain, Russia, Estonia, Ukraine, Armenia, Georgia, Latvia and Israel.

In 2015, Sergey Ostrovsky created a string ensemble, the ‘Solistes de Neuchâtel’, and in 2023 the ‘Ensemble Symphonique de Genève’. Sergey Ostrovsky's role as artistic director of the’ Ensemble Symphonique de Genève’ is multifaceted, both as an ‘artistic manager’ and as a musician ‘involved’ in the performances. From the latter point of view, he will be able to conduct the orchestra from the podium but also conduct the violin as a soloist.

As a chamber musician, Sergey Ostrovsky has played in the world's most prestigious venues, including Carnegie Hall, Alice Tully Hall, the Louvre Auditorium, the ‘Théâtre du Châtelet’, London's Wigmore Hall and the Sydney Opera House. His ‘Aviv String Quartet’ has also made numerous recordings (Hoffmeister, Dohnanyi, Shostakovich, Schubert, Schulhoff, etc.), some of which have received critical acclaim.

Varvara Vasylieva is a Ukrainian violinist based in Berlin. As a soloist over the last few years she performed with the Sinfonieorchester Basel in Stadtcasino Basel, the Mriya Orchestra in Die Glocke, Laeiszhalle and Berlin Philharmonie and regularly gives concerts with the Kyiv Philharmonic Orchestra.

She is a laureate of several competitions, such the Max Rostal International Competition (2nd Prize), the Odesa International Violin Competition (3rd Prize) and the Ysaÿe International Music Competition (1st Prize) among others.

Varvara finished her Bachelor at the Hochschule für Musik Basel in classes of Prof. Barbara Doll and Claudio Martínez Mehner and currently pursues her Master Degree at the Hochschule für Musik Hanns Eisler, Berlin with Prof. Antje Weithaas.

She has actively participated in numerous festivals, such as the Zwischentöne Engelberg, Beethovenfest Bonn, Riehener Serenaden, Im Spiegel, Fiskars Summer Festival and performed alongside inspiring musicians such as Valentin Erben, Claudio Martinez Mehner, Rafael Rosenfeld, Winfried Rademacher, and Silvia Simionescu to name a few.

Since 2023 she’s a founding member of the Arda String Quartet.

Varvara is currently playing J. B. Vuillaume made in 1866 generously on loan from Wilhelm Geigenbau.

The Arda String Quartet is a young string quartet based in Basel. The ensemble was formed in 2023 by four musicians from four different countries who had a passion for string quartet. The quartet has been studying at the Hochschule für Musik Basel FHNW with Jiří Němeček, Rainer Schmidt, Claudio Martinez Mehner and others.

In 2024, the Arda String Quartet was awarded a special prize at the Orpheus Chamber Music Competition in Bern, Switzerland. Through the competition, they were invited for a recital at the Swiss Chamber Music Festival in Adelboden 2025. In the same year they also performed in the Le Vent sur l’Arbre Chamber Music Festival in France and the Altstadtserenaden concert series in Basel.

The Arda Quartet has participated in many masterclasses at the HSM Basel and abroad at string quartet academies such as the Festival Guadix Clásica in Spain, Danish String Quartet Academy in Denmark, Musique à Flaine in France and Geneva International String Academy in Switzerland. Through masterclasses the quartet has had the opportunity to work with wonderful musicians such as Valentin Erben, Jonathan Brown, Cibrán Sierra, Robert Levin, Alina Ibragimova, Miriam Fried, Tim Frederiksen, Ilya Gringolts and Noemie Bialobroda among others.

In 2025 the Arda String Quartet became part of the international chamber music network Le Dimore del Quartetto.

First violin: Varvara Vasylieva
Second violin: Aino Yamaguchi
Viola: Charlotte Lefebvre
Cello: Nadzeya Kurzava

Elizaveta Brakhman was born in 2005 in Nizhny Novgorod, Russia. She has been playing the violin since she the age of 4. Elizaveta is currently studying at the Tel Aviv University, Buchmann-Metha School of Music with professor Hagai Shaham. Her previous education included Central Music School in Moscow where she was studying with professor Evgeny Bouchkov.

Elizaveta took participated to several academies: Keshet-Elion (Israel), Perlman Music Program (USA, Israel), Lancaster International Academy (USA), Solsona AIMS Academy (Spain).

Elizaveta was a member of Yuri Bashmet Young Symphony Orchestra. She toured with the orchestra in Asia (Singapore, South Korea), Germany (Berlin Philharmony), and all over Russia. In 2023 Elizaveta took part in America-Israel Cultural Foundation and won one of the highest prizes.

At above-mentioned academies she took classes with Ilya Kaler, Sergey Ostrovsky, Izhak Rashkovsky, Ulf Wallin, Dora Schwarzberg, Tatiana Samuil, Alena Baeva, Michaela Martin, Aylen Pritchin, Nikita Borisoglebsky.

Australian violist Raphael Masters has recently completed his Bachelor of Music at the Colburn School under the tutelage of Tatjana Masurenko. Notably, he has professionally performed with renowned orchestras such as the Los Angeles Philharmonic, LA Chamber Orchestra, Sydney Symphony Orchestra, Melbourne Chamber Orchestra, and the Philharmonia Orchestra in London, where he held the No. 2 seat.

Raphael's solo engagements include performances at Carnegie Hall and the Sydney Opera House Concert Hall. He has served as Principal Viola of the New York String Orchestra, the Colburn Orchestra, and the Australian Youth Orchestra. Raphael has also performed at the Saline Royale Academy in France and the Rome Chamber Music Festival.

Since 2021, he has been a featured recitalist at St. James in Sydney. Additionally, Raphael has participated as a Chamber Music Artist at the Edinburgh International Festival and has recorded with Ensemble Apex.

He has collaborated in chamber music settings with artists like Noah Bendix-Balgley, Jon Kimura Parker, Clive Greensmith, Arnaud Sussman, and Jennifer Stumm. His mentors include Paul Coletti, Yura Lee, Stuart Johnson, Roger Benedict, and Tatjana Masurenko.

Raphael is grateful to AMF for their continued support of his musical endeavours. He performs on a modern instrument and bow generously loaned by The Colburn School. In 2024, he will pursue a Master’s degree at the Music and Arts University of the City of Vienna under the guidance of Jennifer Stumm.

Theresa Horejsi was born into a family of musicians in 1999. Starting with the violin, she often took part in the "Jugend Musiziert" competition and gained experience in orchestras and chamber music ensembles from an early age. She discovered the viola through her family.

She studied from 2018 at the Cologne University of Music and Dance in the class of Matthias Buchholz and is currently studying at the haute ecole de Musique de Lausanne with Tatjana Masurenko.

She has worked as a chamber musician with Jörg Widmann, the Minguett Quartet, Harald Schoneweg, Gregor Schwellenbach, Robert Kulek and Daniel Haefliger. She has participated in recordings for the Arte Film "TRANS - I Got Life", which was broadcast on television in September 2023.

In September 2023, she took part in the prestigious ARD Music Competition. In March 2024, she takes up a 3. Soloposition in the St. Gallen Symphony Orchestra.

Violist Julian Seney has performed in venues such as the Walt Disney Concert Hall, Carnegie Hall, and Beijing Concert Hall, under conductors Susanna Mälkki, Michael Tilson Thomas, and Gustavo Dudamel, among others.

He is an alumni of the Perlman Music Program, Yellow Barn, and the Lucerne Festival Academy, and has participated in residencies through both Perlman Suncoast and the Lake Champlain Chamber Music Festival.

He is a proponent of new music, and has premiered many works of his peers and mentors—most recently solo with Yale’s New Music series.

In addition to classical music, he also regularly performs as an improviser and has collaborated with Anthony Coleman and Joe Morris. Hailing from Los Angeles, he studied as an academy student with Paul Coletti at the Colburn school.

He received a Bachelor’s of Music from the New England Conservatory, having studied with Kim Kashkashian, and now is pursuing a Masters of Music at the Yale School of Music with Ettore Causa.

Mila Gafner, born in 2004, started playing the viola at the age of 6 at the Lausanne Conservatory. She will then study with Noémie Bialobroda and joined the Pre-HEM program in 2018.

Mila has been a three-time winner of the Swiss Youth Music Competition in solo viola, as well as three times in chamber music. In April 2020, she was a finalist in the international Anton Rubinstein competition in Berlin and received the Förderpreis for the best interpretation of a contemporary work.

Mila has participated in masterclasses with violist and composer Garth Knox, violinist Gilles Apap, the Sine Nomine Quartet, and violist Matthias Buchholz. During the summers of 2018 and 2019, she attended the AIMS International String Academy in Solsona, Spain, and in December 2019, she studied with the Ensemble Modern in Frankfurt, specializing in contemporary music, before joining them on tour in Germany, Amsterdam, and Antwerp.

In 2023, she recorded Kodály's Intermezzo for string trio with her ensemble for the 4 Seasons festival album.

Since 2022, Mila has been studying with Jean Sulem at the CNSMDP in Paris.

Haru Ogiwara, born in London in 2004, embarked on his musical journey at the age of six under the tutelage of Dr. Oliver Gledhill in the cello program at the Guildhall School of Music & Drama's String Training Course. In September 2016, he was admitted to the Royal College of Music Junior Department, where he studied with Michal Kaznowski and Pal Banda, ultimately graduating in 2023 with the prestigious Freda Dinn and Ida Mabbet Prize.
Currently, he is under the guidance of Prof. Hannah Robets at the Royal Academy of Music, benefiting from a full scholarship.

He is a soloist, chamber musician, and orchestra member and has received numerous honours and performances in various music festivals in Europe, include winning the Premier Cup & Recital Prize at the North London Festival, being named the Gregynog Young Musician String Player of the Year 2020, receiving the Masterclass Award at the Gustav Mahler Competition in Prague 2021, and earning the Special Award at the Radolfzell Music Festival in Germany. He also participated as an active student at the Kronberg Academy's Cello Masterclass with Gay Homan in 2022.

Haru's performance venues have ranged from prestigious concert halls such as Cadogan Hall, Wigmore Hall, Ongakudo in Kanazawa, Japan, and historic landmarks like St James Palace, No.11 Downing Street, and the Handel House to esteemed festivals and events like the Youth Music Award Grand Ceremony. His repertoire includes commanding solo performances, including the Haydn Cello Concerto No.2 in D Major with RCMJD Orchestra, Schumann Cello Concerto in A minor conducted by Thomas Gregoy with the Fortismere Community Symphony Orchestra. In 2023, he held a sold out Elgar Room recital at the Royal Albert Hall London with the pianist Craig White, and a solo performance at the Wigmore Hall, London.

Haru has been generously supported by the DES Music and Dance scheme, Awards for Young Musicians, Future Talent, Drake Calleja Junior Scholarship, Wrightson Trust Music Scholarship, J & M Michael, J & A Beares, the Royal College of Music and the Aud Jebsen Scholarship at the Royal Academy of Music.

He plays a cello by J.F. Wright, Newark, 2023 (1727 Goriller Ex Shapiro Model) and a William Salchow bow thanks to the support of Pei Sian Ng and Pei Jee Ng, who have played a pivotal role in nurturing his artistic development.

Arne Zeller, born 4th October 2006, started playing the cello at the age of six and joined the class of Peter Bruns at the HMT Leipzig as a junior student aged 14. Since October 2024 he is a bachelor student in the class of Frans Helmerson at Kronberg Academy. Regular masterclasses with Jens Peter Maintz have been contributing additional important artistic impulses since 2021.

Being the winner of the Grand Prix and audience prize of the Budapest International Cello Competition 2025 and the first prize (ex aequo) of the International Pau Casals Award 2024, he is increasingly gaining international attention.

Further important awards in his career were the first prize of the International Anna Kull Cello Competition (Graz, 2020), the first prize of the International Mahler Cellocompetition 2022 and the second prize at the 29. International Brahms Competition (Pörtschach 2023). He also is an awardee of numerous first national prizes and special prizes of the federal German competition „Jugend musiziert” in the categories Cello solo and chamber music and is since 2024 the current holder of the Pergamenschikow Scholarship of Kronberg Academy.

Arne debuted with Tchaikovsky’s Rococo Variations at 13 years of age, soloistic performances followed with the Baden-Baden Philharmonics, the Euro Symphony Orchestra, Kremerata Baltica, the Franz Liszt Chamber Orchestra and the National Philharmonics Budapest with works by Korngold, Dvorak, Shostakovich, Boccherini, Haydn, and Weinberg. In 2023 he repeatedly soloed with the Frankfurt Radio Symphony Orchestra at the “hr-schooltour”, and the University Orchestra Mainz to relate classical music to school students. During his studies at Kronberg Academy he is also regularly involved in concerts targeting social involvement issues.

In addition to his performances as a soloist, Arne Zeller regularly plays public concerts in varying chamber music formations, for example at the Moritzburg Festival, the Heidelberger Frühling, the Con Spirito Festival Leipzig, the Rheingau Musik Festival, the Nymphenburger Sommer, the Bachwoche Ansbach, the Berner Seefestspiele, and the Kronberg Festival.

Particularly formative experiences in chamber music he experienced as junior artist at “Chamber Music Connects the World” at Kronberg, at the Geneva International String Academy, the Henle Chamber Music Academy, and the soloist program of the Verbier Festival. In this context he was privileged to already perform together with artists like Gidon Kremer, Antje Weithaas, Sergey Ostrovsky, Noémie Bialobroda, Lawrence Power, Valentin Erben and Steven Isserliss.

He played at venues like the Musikverein Wien, Alte Oper Frankfurt, Laeiszhalle Hamburg, the Liszt Academy Budapest, in the Conservatoire de musique de Genève and the Casals Forum Kronberg.

Other important impulses were set through masterclasses with Ivan Monighetti, Hans Jørgen Jensen, Jan Vogler, Gary Hoffman and Steven Isserlis as well as Sir Andras Schiff, Gidon Kremer and Martin Helmchen.

Arne Zeller holds scholarships by the „Studienstiftung des Deutschen Volkes“, the „Deutsche Stiftung Musikleben”, the International Music Academy Liechtenstein and the Villa Musica Rhineland-Palatinate. He receives funding by the Peter-Klöckner Stiftung and was awarded the Martin-Stadtfeld-Prize, the Werner Stiefel Prize Baden-Baden, and the Lichtenberger Musikpreis.

He is kindly supplied with the Charles Maucotel cello „ex-Tortelier“ (1850), courtesy of a member of the Stretton Society, which also strongly supports him through the “Stretton Exellence Membership Programm” since 2024.

In 2026 Arne Zeller has scheduled concerts as a soloist and as a chamber musician in Germany, Hungary, Switzerland, Italy, Austria, Greece, Romania, Spain and Japan.

Daphne Richman Poleg, born in 2003 in Israel, is  a graduate of the Thelma Yelin School of Arts, the Israeli Conservatory of Music in Tel Aviv and the Jerusalem Music Center Mishkenot Sha'ananim. She is currently a student in Professor Hillel Zorri's class, during her third year of her bachelor's degree in performance at Buchmann Mehta School of Music at the Tel Aviv university.

Daphne is first prize winner of Paul Ben Haim 2020 competition, competition of the Israel Conservatory of Music in 2019 and 2015. She received from the Sharett Foundation a scholarship with extra distinction 2019 -2024, and scholarships from the Ronan Foundation in 2018, 2019, 2023.

In February 2024 she played a full recital that was broadcasted live on the radio. In June 2023 she played with her piano quartet in a live broadcast for voice of music. In November 2019 Daphne was chosen to represent the Tel Aviv conservatory of music and played a full recital. In November and May 2018 she played with the chamber ensemble of the Goldman program.

In April 2024, Daphne received a certificate of honor for outstanding achievement - the BMSM. She was chosen to participate In two projects of the Israeli Philarmonic in April 2023 and February 2024. She was principal cello in the Buchman Mehta Symphony Orchestra from 2022 to 2024, principal cello in the Young Israel Philharmonic Orchestra from 2019 to 2021, principal cello in The Thelma Yellin Symphony orchestra from 2019 to 2021.

In 2023 she participated in Keshet Eilon mastercourse, and played in a piano quintet with Sergey Ostrovsky, and was chosen to play solo in the gala concerts In Keshet Eilon and Tel Aviv Museum of Art.

In 2015 and 2022 Daphne participated in the "Aims" summer festival in Spain where she played solo and chamber music in several concerts. In 2018 and 2020 she participated in the prestigious "Huberman" program of the Jerusalem Music Center, in which she traveled to Switzerland and Italy, where she played solo in celebratory concerts in Italy, Switzerland and the Culture Hall in Tel Aviv.

In June 2022 Daphne flew on behalf of the Jerusalem Music Center Mishkenot Sh'aananim to solo and chamber concerts in Switzerland. She participated in master classes with Gary Hoffman, Frans Helmerson, Amit Peled, Hans Jürgen Jensen, Orpao Mendozzi, Emmanuel Gruber, Alessandro Adriani, Zvi Pelser, and in Yitzhak Perlman's Genesis program.