Bought as a kit from AliExpress. Haven't got any more info and don't even know what kind of driver tube is used; the print on the tube is rubbed off, but propably it's a 12AT7 or 12AX7, but could also be a 6N1P.
There were som points that were unclear, and instructions were even a bit contradicting. However in the end I got it all together and then made a go make it more complicated by adding a relayboard switching the inputs. Another "problem" was the mains transformer (and the need for a second transformer, powering the selector). How to best mount the transformer(s)?
Due to the "problems", nothing much has been done, unfortunately. The project is waiting for some screws, some wires and some determination.
This is a wild guess. How does a schematic look like for this one??