The Spiegel String Quartet was founded in 1996 and consists of Elisa Kawaguti and Stefan Willems, violin, Leo De Neve, viola, and Jan Sciffer, cello.

Due to the almost exclusive concentration on the quartet and the deep affection for the string quartet repertoire, the Spiegel Quartet achieved from the very first concerts an international reputation. Since then the Spiegel String Quartet has put in guest appearances at a variety of music festivals and important halls in Europe and South Africa, such as Société Philharmonique de Bruxelles, deSingel Antwerpen, Festival van Vlaanderen, Concertgebouw Amsterdam, Théâtre du Châtelet Paris, MUSICA Strassbourg, La Société de Musique de Chambre de Lyon, Frits Philips Eindhoven, Vrijthof Maastricht, De Doelen Rotterdam, Meistersingerhalle Nürnberg, Philharmonie Duisburg, Gesellschaft für neue Musik Mannheim, NDR Hannover, Berliner Konzerthaus; Villa Musica Mainz, Schleswig Holstein Festival, SDR Bern, Dartington Summer School, Huddersfield Contemporary Music Festival, BBC Belfast,Blachheath Halls London, Jeunesse Musicale Vienna

In its repertoire Spiegel String Quartet does not restrict itself to the performance of works from a single stylistic period. Quite the reverse, in fact: in addition to the great, timeless masterpieces by Beethoven, Schumann, Schubert, Brahms, and so on, the quartet also interprets contemporary and occasionally controversial works such as 'Black Angels for electric string quartet' by Crumb, or works of Celis, Shostacovich, Xenakis, Pintscher, etc.In addition, the Spiegel String Quartet has become a source of inspiration in its own right for contemporary composers. Many works have been written for and with the quartet members in the last few years - creations which have engendered an enormous following, both in concert halls and on CD. In fall 2000 Spiegel String Quartet created the third quartet by the Italian composer Ivan Fedele in Brussels, Rotterdam, Duisburg and Paris. Musical partners are the pianists Gülsin Onay, Stephen Kovacevich, Joanna MacGregor, Bernhard Wambach, Florent Boffard, the accordion player Teodoro Anzellotti and clarinetplayer Jörg Widmann.