Bring Power to your Modules

Every Eurorack Synth needs a power bus. The power bus is the central connection point between the power supply and each module in your rack. A good bus is short, able to handle enough power and convenient to use.

Why short? Because shorter distance between each connector limit the impedance on the power rails between each module. The impedance on the ground rail (the 0 Volt reference) needs to be as low as possible. Having short copper tracks reduces that impedance.

With the Eurorack Power Bus - 28, you can connect and power up to 28 Eurorack modules at once!

This board only needs + and - 12 V power supply. +5 V is generated by an on-board linear regulator. Screw Terminals are versatile and let you connect your bus to any kind of power supply.

3 LEDs are present to show you if there's energy on the rails, and if the polarity is correct.

The bus is totally assembled. No solder required.

Want smaller or want to solder?

Check my other bus boards:

• The Compact Power Bus (10 connectors) - DIY Friendly
• The Eurorack Power Bus - 14 (14 connectors)
• The Eurorack Power Bus - 18 (18 connectors, DIY Friendly)
• The Eurorack Power Bus - 26 (26 connectors, DIY Friendly)

What makes it special?

It's compact, affordable, and easy to use. You only need a 3-rail PSU (-12, 0, +12V). +5V is generated by the bus board itself. The PCB is 25 cm x 6 cm. Easy to integrate within a 84HP row.

8 Screws per board and 1.6mm thickness make the PCB really stiff and you can pull and push connectors without a problem.

More information on my Blog

About +5V On-Board Linear Regulator Option

If your Power Supply doesn't provide the +5V Rail, you can choose the option "On-Board +5V Linear Regulator". The +5V rail will be regulated from the +12V rail by a LM7805 Linear Regulator. The LM7805 can deliver up to 1.5A, but please note that it will draw this current from the +12V Rail. Also, Linear Regulators heat a lot.

So please, if you plan to draw a lot of current on +5V Rail (lot of modules with micro-controllers), consider using a PSU that can provide directly the +5V and choose the option "NO +5V Regulator".

About connectors

HE-10 Connectors are keyed: they limit the risk to connect the modules in wrong polarity. But, you absolutely need to check your wiring twice before powering the bus!

Always check voltage polarities and the power connector pinouts of the modules before powering anything!