The Ypsilon Phaethon presents the opportunity to make some « tube rolling » depending on the boards integrated in the amplifier. Since few years, by changing configuration through jumpers, you can use 5687 (and alternates like E182CC and 6900) or 6H30 tubes. In the following documents you would find a video (in french) done by the french distributor (Musicadomia) explaining the 2 possible configurations and a PDF document showing the jumpers positions.
