Complete PCB SET for high end preamp: https://www.vaneijndhoven.net/jos/relaixedsmd/index.html
https://www.vaneijndhoven.net/jos/relaixed2/index.html - OLED display
Full doc: https://www.vaneijndhoven.net/jos/relaixedsmd/index.html
costs 30$ + shipping
https://www.vaneijndhoven.net/jos/relaixed2/index.html - OLED display
Full doc: https://www.vaneijndhoven.net/jos/relaixedsmd/index.html
RelaiXedSMD -- DIY balanced pre-amplifier
2 PCBscosts 30$ + shipping