Software synthesizer

A software synthesizer, also known as a softsynth, is a computer program, or plug-in that generates digital audio, usually for music. Computer software that can create sounds or music is not new, but advances in processing speed are allowing softsynths to accomplish the same tasks that previously required dedicated hardware. Softsynths are usually cheaper and more portable than dedicated hardware, and easier to interface with other music software such as music sequencers.

Dedicated hardware synthesizers can have software as complex as a soft synth. The distinction is that softsynths run on a general purpose computer with a sound card, and the hardware (dedicated) synthesizers have the custom software built-in. The advantage to dedicated hardware is that it can be more stable, and also that it often has a user interface that is physical (knobs and sliders) and therefore easier to manipulate during performances. Many softsynths use mathematical algorithms that directly emulate the electronic components and circuitry of the original hardware synthesizer. This produces an exceptionally authentic sound, even capturing "flaws" in the original hardware, such as oscillator drift caused by thermal sensitivity of the components.

Many popular hardware synthesizers are no longer manufactured, but have been emulated in software. The emulation can even extend to having graphics that model the exact placements of the original hardware controls. Some simulators can even import the original sound patches with accuracy that is nearly indistinguishable from the original synthesizer. 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 softsynths are heavily sample based, and frequently have more capability than hardware units, since computers have fewer restrictions on memory than dedicated hardware synthesizers. Some of these sample based synthesizers come with sample libraries many gigabytes in size. Some are specifically designed to mimic real world instruments such as pianos. Many sample libraries are available in a common format like WAV or SoundFont, and can be used with almost any sampler based softsynth.

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