Hmmm... This thread is rapidly degenerating into the same "I believe in one God the Father Almighty" series of dogmatic exchanges as the recently deceased "Best Transport Poll" thread - i.e. a thread in which no-one is prepared to:
a) Agree on the definition of what constitutes a "component"
b) Agree on whether or not "biggest effect" should be positive or negative
c) Agree on the definition, as implied in the title, of "sound"
Taking a), one question has to be whether or not the 'room' constitutes a 'component' or is, in fact, the de facto environment for listening. In the same vein, should we also question whether or not 'mains feed', 'equipment support', 'cable elevator blocks', Shakti stones, etc. also qualify as 'components'?
Under b), I've long held the belief that no component can 'improve' the sound of any signal passed though it - all it can contribute to the process is to do the least 'damage' to the sound. Under this umbrella caveat, all 'effects' will be negative, in that they will 'damage the sound'. The best components will do the least damage (i.e. have the 'smallest effect'), while badly designed/built components could do significant 'damage to the sound' (i.e. have the 'biggest effect').
As far as c) is concerned, we've already had posts that differentiate between the effects of components on 'sound' and on 'music'. For me, its all about the music and how a system communicates the music and its various aspects (including spatial aspects such as imaging and soundstaging). I battle to understand the relevance and/or importance of 'sound' as used above if the 'musical' aspects are all addressed.
Until we all agree on the definitions and how they apply, this debate will comprise people arguing at cross-purposes and will not produce any meaningful consensus...
Pity!!