The interaction of elements that when combined produce a total effect that is greater than the sum of the individual elements.
Many audiophiles believe the best way to achieve audio synergism is to purchase all of their components from the same manufacturer. However, I have found great success in incorporating a variety of audio components in building my system which in my opinion, yields a musical presentation that is more complete than one comprised of all the same manufacturer's components. Every consumer electronic manufacturer has their own individual design ideas of the circuitry that they believe will reproduce the best sound. Furthermore, since no audio component is perfect, a combination could in theory, bring you closer to that state. It is my belief that using a variety of high-end quality components that are synergistically put together, will provide a more unique and fulfilling sound by creating a symbiotic relationship between different audio designers yielding a positive-sum gain from the varied combinations.