Eurorack

The Doepfer A-100 is an analog modular synthesizer system introduced by German audio manufacturer Doepfer in 1995. Although it only had 10 modules at time of release, it currently has more than 120 modules plus several different enclosures and accessories.

A-100 modules are designed to be rackmounted, each being 3U tall and a multiple of 2HP wide, though a variety of cases are available to house them. This type of racking system, 'Eurorack', has been adopted by many other manufacturers of synthesiser modules. Modules are patched using standard mono miniature (3.5 mm) leads. This combination of 3U height, multiples of 2HP width, and 3.5 mm leads is known more generally as the Eurorack standard, and is in contrast to the older combination of 5U height and 6.35 mm leads pioneered by Moog. Other companies such as Analogue Solutions, Analogue Systems, Roland, Moog and Cwejman have also adopted the Eurorack standard, making it relatively easy to integrate their modules into each other's systems.

Using certain modules designed specifically for the purpose, it is possible to use the A-100 system to emulate a Trautonium or a Theremin, as well as to use it as a vocoder.

The following modules have been, or are still being, manufactured by Doepfer:

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