Beat Zampler is a free sample workstation from Beat in collaboration with Synapse Audio. This sample workstation loads SFZ files which provide the wav-samples for the oscillators. Synapse Audio borrowed various elements of Zampler from the synthesizer DUNE, including the modulation matrix. This can also be seen in the graphical interface.
Zampler is available for Windows and Mac. Below you can listen to some audio demos of this sample workstation: