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 passive RIAA equalization network (series resistor-less, dynamics preserving), driving the powerful 6N6P or 5687 double triode on the output stage
LPU I, LPU II and LPU III family of Phono Pre-Amplifiers share similar tube input stage- a pair of EF86 pentode tubes. Due to the brilliant sound character of the EF86 those tubes were commonly used in many radios and RTR tape recorders in the early 60s. The idea of their circuit design was borrowed from the input stage of early Reel to Reel (RTR) tape recorders, which were used in the mastering studios and radio stations. Maybe that is one of the reasons as why most recording from the 60s are sounding at their best, much better than from the 70s and 80s? In a way, the EF86 input tube design closes the loop and makes all our LPU Phono Amps range a time-less classic.
We do not recommend purchasing a key system component without first auditioning it carefully, which is why we have demonstration rooms and a 14 day trial period policy. However in certain situations it can be difficult for people to get to our showroom and for those instances we can offer our mail order service.