hi folks, can someone explain to me the way modular rack units work? I am familiar with euro only.

1) Are all (most) racks heights measured in U?

2) Euro has the width concept of HP. There are 84 per 19" rack. I think in general these can be thought of as possible module positions. Another way of looking at it is they define the minimum module width, and all module widths are a multiple of them. Is there a similar concept in non-euro formats? I probably only need a few examples.

Thanks,

Doug

## Modular Rack Units

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For rack height - 1 rack unit is 1.75" high. That's the standard.

http://en.wikipedia.org/wiki/Rack_unit

Obviously Euro and Frac are 3U tall. Wiard 300 and Modcan A (in a rack frame) are 6U, MOTM/DotCom/Modcan B are 5U, Serge and Buchla are 4U...

http://synthesizers.com/formfactors.html

A "standard" Frac Rack (PAIA, Blacet) has basically 10 "spaces" for modules. Each space is 1.5" wide. Your average Blacet module is 2 spaces wide. That leaves you with "ears" which are basically useless.

Looks like some people are making new Frac Racks/cases that are 11 spaces wide (Bug Brand, Dragon's Lair).

http://en.wikipedia.org/wiki/Rack_unit

Obviously Euro and Frac are 3U tall. Wiard 300 and Modcan A (in a rack frame) are 6U, MOTM/DotCom/Modcan B are 5U, Serge and Buchla are 4U...

http://synthesizers.com/formfactors.html

A "standard" Frac Rack (PAIA, Blacet) has basically 10 "spaces" for modules. Each space is 1.5" wide. Your average Blacet module is 2 spaces wide. That leaves you with "ears" which are basically useless.

Looks like some people are making new Frac Racks/cases that are 11 spaces wide (Bug Brand, Dragon's Lair).