Push Pull 6550 DIY audio tube amps

The idea of building a DIY audio vacuum tube amplifier based on high-quality materials begins in the early 90's. Initially had to answer the question "Classic Push Pull or a Single ended amp ?" So starting the design somewhere in 1994 I decided to design οn a blank piece of paper, a pair of monoblocks push pull tube amps with a power supply in a separate chassis which would not use solid materials but rectifier tubes.