The Sontec EQ is a nice great and outstanding Equalizer with history. The Original Idea and Design was made by Burgess MacNeal and George Massenburg for the first parametric Equalizers. You can find a nice retrospective here on the Universal Audio Website.
We ordered the PCBs from Igor in December 2012.
A good help is the Sontec Building Thread at DIY Group Forum
Our stores where Reichelt.de, Mouser, Alphastat, Segor Berlin
We can’t find any 55K Resistor at Reichelt.de, so we had to build a 55K Resistor based on a 49.9K and a 5.10K Resistor.
One of our girlfriends wants to solder too, so we showed her how to do it.