The phono pre-amplifier is based on a classic all valve circuit design used to master vinyl recordings and master tapes.
It is a two gain stage design consisting of 2 (one for each channel) pentode valves on the input and one double triode valve on the output.
The input stage utilises lush sounding EF86 valves in pentode mode, which are loaded by active RIAA equalization network (series resistor-less, dynamics preserving), driving the powerful 6N6P or 5687 double triode on the output stage.
