Not so much a philosophy as a vision of what could be accomoplished. Without question, Nelson Pass has been a visionary in the arena of high end audio since the mid 70s. Few are his peer,period. Remains dedicated to two channel audio and continues to push the audio envelope to loftier heights with each design. His gear sounds the way it does, because in all reality he is a Physicist, not an electrical engineer.
Pressed to mention one piece that started high end,I would have to say the Threshold 400A. Was present at its debut. Few products have a mesmerizing effect on people,but I remember that night very well some 28 years later. All who were present were just stunned by the sonics of this amplifier, beliefs were truly shaken to the core that night.One would had to be there to see the expressions on the audiophile faces that night. That period of time when solid state finally delivered the promise that had been expected. In fact a week later I bailed out of all my tube gear and went with Threshold and haven't looked back since. I was already 20 years into this hobby and was probably getting ready to leave it,when the Threshold debuted. Been firmly entrenched in the Nelson Pass camp ever since.
But no doubt in my opinion of 48 years in this, the debut of the Threshold 400A, was a pivotal moment in audio. With the introduction of Threshold, Nelson Pass not only raised the bar of achievement but clearly redefined the role of audio components. And in doing so created a dimension that was to become as we now know High End Audio.