Modular Form Factors
There are two dominant modular synthesizer form factors:
Moog Unit - also called MU or 5U, is a large, full-figured module format. This is the format built by Synthesizers.com. MU is 8.75" tall (5U) and comes in widths of 2.125" which is 8 spaces in a 19" rack. Modern MU uses the same panel size as Moog modulars but uses the Synthesizers.com power connector which has become a standard. Power is +/-15v and +5v. MU uses large knobs and 1/4" jacks. Panels are typically black with exposed metal flanges on each side. Enclosures can be hardwood, portable or 19" rack.
EuroRack - is the popular small format at 128.5mm tall which is about 5" and close to 3U. Eurorack uses the smaller 3.5mm jacks and usually smaller knobs. Power systems for Eurorack use a flat cable to provide +/-12v,5V. Panels are a variety of colors, often silver. Typical enclosures are boxes, foldable or 19" rack.
Other form factors are less common but still available:
FrackRack - is 3U tall (5.25"), uses a power connector like MOTM with +/-15v and 3.5mm jacks. Frackracks are close to Eurorack and they can be used together with certain considerations. Panels are a variety of colors, often black. Enclosures are typically 19" rack.
MOTM - 5U = 5x1.75"=8.75 tall like MU, but comes in different width increments and has a thick flat panel. MOTM uses a 4-pin power connector to provide +/-15v, later offering 5v. MOTM modules use 1/4" jacks. Enclosures are typically 19" rack.
4U - 4x1.75"= 7" tall panels, typically flat and silver. These include Buchla, Serge and others. Connectors are often a combination of banana jacks for control signals and 3.5mm for audio. Power is typically +/-15v but vary in connector style. Enclosures are typically 19" rack but sometimes foldable boats. 4U systems often are used without a traditional keyboard controller.
This list shows some of the common modular patchable synthesizer makers and form factors - modern and vintage.
Manufacturer | Model | Format | Connector | Height | Smallest Width |
Power |
---|---|---|---|---|---|---|
Moog | 900 | MU | 1/4" | 8.75" (5U) | 2.125" | +12,-6 |
Synthesizers.com | Q | MU | 1/4" | 8.75" (5U) | 2.125" | +15,-15,+5 |
Doepfer | A100 | EuroRack | 3.5mm | 128.5mm (~3U) | 10mm (.4") | +12,-12,+5 |
EuroRack | Modular | EuroRack | 3.5mm | 128.5mm (~3U) | 10mm (.4") | +12,-12,+5 |
MOTM | Modular | MOTM | 1/4" | 8.75" (5U) | 1.75" (1U) | +15,-15 |
Modcan | B Series | MOTM | 1/4" | 8.75" (5U) | 1.75" (1U) | +15,-15,+5 |
Blacet | Modular | FrackRack | 3.5mm | 5.25" (3U) | 3" | +15,-15 |
Paia | 9700 | FrackRack | 3.5mm | 5.25" (3U) | 1.5" | +15,-15 |
Paia | 2700/4700 | 3.5mm | 4" | 2" | +9,-9 | |
Buchla | 100/200/200e | 4U | Banana & TiniJax | 7" (4U) | 4.25" | +15,-15,+5, +12,+24 |
Serge | Modular | Rack | Banana | 7" (4U) | 17" | +12,-12 |
Polyfusion | 2000 | 1/4" | 7" (4U) | 3" | +15,-15 | |
PPG | 300 | 1/4" | 220mm | 110mm | +12,-12 | |
Steiner-Parker | Synthasystem | 3.5mm | 150mm | 45mm | +12,-12 | |
EMU | 2000 | 1/4" | 6" | 3" | +15,-15,+5 | |
ARP | 2500 | 3.5mm | 8" | 3" | +15,-15,+12 | |
Roland | 100M | 3.5mm | 230mm | 104mm | +15,-15,+22 | |
Digisound | 80 | 3.5mm | 9" | 3" | +15,-15,+5 | |
Aries | 300 | TiniJax/3.5mm | 9" | 3" | +15,-15,+5 | |
Modcan | A Series | Banana | 9" | 2.25" | +15,-15,+5 | |
Cynthia | A Series | Banana | 9" | 2.25" | +15,-15,+5 | |
KB Elec. | Wavemakers | 1/4" | 10" | 2" | +12,-12 | |
CMS | Modular | 3.5mm | 10.3" | 3" | +15,-15 | |
Wiard | 300 | 3.5mm | 10.5" (6U) | 2.83" | +15,-15 | |
Roland | 700 | 1/4" | 11" | 2.56" | +15,-15,+14.4 | |
Technosaurus | Selector | 1/4" | 15.75" (9U) | 1.6" | +18,-18 |
Special thanks to: Sam, Mike, Mark, Steve, Bernie, Nicola, Andre, Steve, Ruud, and John for helping me collect this information. -Roger.