Sigma11 Power Supply for Dummies

This article is about the Sigma11 power supply, I built it for my Gamma2 DAC to see if a dedicated power supply would bring any improvement over USB power or a simple wallwart psu. Since this project is going to power a device that would normally be powered by USB I will be building a 5V power supply!

Parts selection

Sigma11 PCB

This is the bare Sigma11 PCB, bought from

IEC socket

Get a proper grounded IEC socket, I chose a standard version, but if you are so inclined, you could go all in and buy yourself a socket with a built-in filter.

On/Off button

Normally I go for round buttons, but since I decided to place the button on the back-side I used a rectangular one for this project. The advantage to the round buttons is that the hole for those can be drilled instead of having to spend half an hour swearing at your multi-tool and the subpar grinding discs you bought!

Fuse Socket

To protect your expensive equipment (and yourself) against shorts and whatnot, please remember to get a fust holder.

Power Out Socket

Building a power supply is fun enough, but if you forget a way to actually connect your PSU to your equipment the only thing you will be enjoying is that "black background" all audiophiles love, not so much because you have reduced hiss, hum and noise beyond you hearing, but because your equipment is not actually ON. Another way of going about this is to simply drill a hole out the back of your PSU, tie a knot on your power chord (on the inside so that accidental pulls do not yank the wire loose inside the case) and just let it hang out.

Transformer (toroid)

We also need a toroid with 9V secondaries (these will be connected in parallel for this project).


Sorry, no pictures here (they will come later, but I do not want to spoil the surprise). Please remember to buy SOMETHING to house your project since having mains wiring lying about is not really all that safe.