The Kurzweil K2000 is a digital synthesizer and music workstation produced by Kurzweil Music Systems between 1991 and 2000 in a variety of standard configurations, including rack-mountable versions and models that came with 16-bit user sampling. The K2000 features a complex digital synthesis architecture dubbed V.A.S.T., which stands for "Variable Architecture Synthesis Technology", Kurzweil's marketing term for the digital signal processing (DSP) sound processing system used in the K2000 and other members of its K2xxx series. Variable Architecture Synthesis Technology (V.A.S.T.) Summary V.A.S.T. stands for variable-architecture synthesis technology. It is variable in that the user can select different signal paths, which contain different DSP functions, for use in creating and shaping a sound. V.A.S.T. also includes an extensive modulation system, similar in concept to that of analog modular synthesizers. A wide array of modulation sources can be assigned to various parameters within a signal path, and modulation sources can be combined to create new modulation sources. Details The basic component of a V.A.S.T. program is a "layer". A layer on the K2000 contains a single "algorithm", which contains up to four slots for user-assignable DSP functions. The algorithm assigned to a layer is preceded by several other functions, or "blocks". There is the "keymap" block, which determines which (if any) samples are assigned to the keyboard in the layer. This is succeeded by the "pitch" block, which determines how the "keymap" is pitched across the keyboard. Following the "algorithm" section is an amplifier block (and a dedicated multi-mode envelope to modulate the gain of the sound over time) and, finally, an "output" block that determines which group of outputs (there are four output groups on the rack version, two on the keyboard version) the sound is assigned to and how it is panned between the two outputs in a stereo group. In essence, therefore, we have: [keymap] - [pitch] - [algorithm] - [amp] - [output] Up to 3 layers can make up a normal "program", and 32 layers for drum programs similar to a "patch" on other synthesizers. [N.B.: 3 layers are possible on the K2500 (3 on the K2000 series) as "Drum Programs" (using any types of patches, not just drums), and may be used on 8 consecutive MIDI channels. The PC3 and K2600 series allow 32 layers on all channels.] Within a program, each layer can have independent settings in all of the various blocks, including different algorithms,