The operating Class is switched to Class A, which is far less efficient - but produces smooth, rich, silky harmonics and warm low end. Many vintage amplifiers were built with this operating class.
Now here is where we get tricky and is the basis of our patent. The wiring configuration is switched as well - from Push-Pull to Single-Ended. This configuration - the first way tubes were ever wired – is again far less efficient but puts emphasis on the even order harmonics. These are the second harmonic that lives one octave above the notes that are being played and they’re the most pleasing of all harmonics. They sound sweet and add a fullness to the sound like no other, almost like a super subtle octaver that is way back in the mix.
Push-Pull circuits cancel out this second harmonic when the wave form is split in half and each half is amplified separately, and the sweet second harmonic is replaced by the punchier odd-order third harmonic… thus the substantially louder impact of the Push-Pull configuration.