Some are specifically designed to mimic real-world instruments such as pianos. Some of these sample-based synthesizers come with sample libraries many gigabytes in size. Some softsynths are heavily sample-based, and frequently have more capability than hardware units, since computers have fewer restrictions on memory than dedicated hardware synthesizers.
Popular synthesizers such as the Minimoog, Yamaha DX7, Korg M1, Prophet-5, Oberheim OB-X, Roland Jupiter 8, ARP 2600 and dozens of other classics have been recreated in software. Some simulators can even import the original sound patches with accuracy that is nearly indistinguishable from the original synthesizer. The emulation can even extend to having graphics that model the exact placements of the original hardware controls.
Many popular hardware synthesizers are no longer manufactured but have been emulated in software. Softsynths can cover a range of synthesis methods, including subtractive synthesis (including analog modeling, a subtype), FM synthesis (including the similar phase distortion synthesis), physical modelling synthesis, additive synthesis (including the related resynthesis), and sample-based synthesis.
