Tube amplifier hybrid power supply

The schematic to the right is based on the Hybrid Graetz Bridge concept after a Fulvio Chiappetta paper, published by the Italian Magazine ‘Costruire HiFi’ a reference for the DIYers. He tested and comparated this topology versus a pure tube vacuum state power supply design with a 300B output tube amplifier and there was no difference both while listening and measuring the output noise spectrum.