Analog Notes

Title link takes you to Analog Notes, a great resource site for modular synths. The following is just an excerpt from the site.

"Modular analog synthesizers are musical instruments that are typically made up of discreet analog electrical circuits. These circuits may be mounted on individual panels, or may be grouped together in various chassis configurations.

While some manufacturers produce modules in sizes that no others make, there are three physical and electrical formats that are used by more than one module manufacturer - "Euro-Rack", the format used by Analogue Systems, Analogue Solutions, Doepfer and Plan B (with minor differences), "Frac-Rack", the format pioneered by PAiA and used by Blacet, Wiard and others, and "MOTM", used by Synth Tech and many other makers. Euro-Rack and Frac-Rack formats use 3U (5.25") of vertical space. MOTM uses 5U (8.75") of vertical space. Typically, this means that the Euro- and Frac-Rack modules use smaller knobs and jacks, while the MOTM modules use larger ones.

In general, european modules use 12v power and modules from the United States use 15v. There are exceptions, as well as some newer modules that use 5v power.

* Modular Synthesizer Comparison Chart
* Synthesizers.com form factor list

One of the biggest decisions you can make is whether to purchase full kits, parts, or pre-built modules. The main analog module kit supplier is Blacet, with a couple available from PAiA. Various parts are available from CGS (Ken Stone), Music From Outer Space, Oakley and others. Most other manufacturers sell complete modules. NOTE: Sadly, as of December 2006, Synthesis Technology will no longer provide full kits, although boards and panels should be made available in February 2007."