EURORACK POWER SUPPLY

What type of eurorack power supply should I choose?

Choosing the right power supply for your eurorack case might be a hard choice especially if you are not really a tech person. Understanding the differences between them is important.

Generally, there are three types of eurorack PSU available:

• Linear PSU
• Switch-mode PSU
• Hybrid PSU

The difference between them is their construction and how the primary AC voltage is converted into the output DC voltage.

Switch-mode power supplies use a power transistor to produce a high-frequency voltage that is passed through a small transformer and then filtered to remove both the AC component and noise. 

Linear power supplies deliver DC by passing the primary AC voltage through a transformer and then filtering it to remove the AC component. 

Switching power supplies feature higher efficiencies, lighter weight, longer hold up times, and the ability to handle wider input voltage ranges. Their disadvantage is that they may generate high-frequency noise resulting from the use of a power transistor.

Linear power supplies don't have the problem of the noise but are limited in capability, less efficient - part of the power is always transformed into heat,  and they tend to be much larger in physical size. Most often they are also more expensive than switching psu.

Interesting alternatives are hybrid psu that use both linear and switch-mode technology. AC voltage is first passed through switch-mode converters and then at the final stage through linear voltage converters. Switching converters removes the necessity of bulky and heavy transformers and linear regulators help to attenuate the noise of the output DC voltage.

How much power do I need for my case?

We always recommend checking what will be your modules set power consumption at +12V, -12V, and +5V lines. Where to find that information? It should available at the modules manufacturer webpages.
What you can also do is to use www.modulargrid.net, and build there your virtual eurorack case. Modulargrid is a huge database of modules with all their technical specifications. Once you fill your virtual case with modules - Modulargrid will calculate the total power consumption of selected modules.