The ZAPP String Quartet is an extraordinary string quartet which is specialized in playing improvised music, jazz, rock, ethnic music, contemporary music and all kinds of combinations of these styles. There is a long string quartet tradition in classical music. the ZSQ adds its own groovy way of playing and percussion techniques to it, which enables them to sound like a heavy rock band, a bulgarian folkgroup or a bebopping jazz band as well.

All the members have a background as improvisors and they all compose or arrange music for the quartet. Additionaly, composers from the Netherlands and abroad regularly compose for the group.