As keyboard workstations began pushing the boundaries of music technology, Kurzweil pioneered sample-playback instruments and embraced innovations in digital signal processing. The K2000 introduced Variable Architecture Synthesis Technology (V.A.S.T.) with complex timbre-shaping algorithms, multilayer signal routing, and optional user sampling. Its successor, the K2500, featured more memory, live audio processing, greater expandability, and superior sample editing. The K2600 upped the ante with even more memory, 20-bit output, and standard features that were previously options.