Synergy because the best piece of gear will do anything coupled with the wrong one...
Once bought...
Adressing the three working dimensions:
Mechanical : Speakers vibrations resonance controls...(other gear vibration is important too but secondary compared to speakers)
Electrical : Wall plug and central panel control of interferences...
But mostly overlooked , the necessary well grounding of dac, amp and preamp...
Acoustical: the system/room various parameters control... Balance between diffusion,reflection,absorbtion and control over these ... What is very overlooked is the power of the Helmholtz resonators by their parameters adjustment and their location to tune and tame a room...