"sound realism" is a correct and usable phrase in written English.
You can use it when you want to refer to a realistic approach or outlook. For example, "He always strives for sound realism in his decision-making."
I don't think that's right: if the songs are rooted in reality, they're not the sound of realism, and there's certainly no hint of earnestness in Williamson's ranting over Andrew Fearn's spartan instrumental backing.
That doesn't sound like realism to me.
The choice seemed sound: gritty realism would be a plausible alternative to Sellars's impassioned surrealism.
Knutson commended the soundtrack's large size and the sound effects' realism.
Not those plastic, flat appliances with 983 instrument sounds and realism that would fool nobody.
The sound and the realism of the military games make me edgy.
But Fox's pledge to maintain Britain's ability to wage war unilaterally, cooperate with France while snubbing the EU's defence agency, cutting Whitehall staff and reforming wasteful procurement (again) does not sound like tough realism, especially when combined with Cameron's gimmicky "war cabinet" and national security adviser approach.
The competitive and greedy view of social relations offered by classical realism sounds a lot like the beliefs that underlie social dominance orientation (SDO).
Almost surely, you'll discover that what sounds like hardheaded realism actually rests on a foundation of fantasy, on the belief that invisible vigilantes will punish us if we're bad and the confidence fairy will reward us if we're good.
Democrats must combine an ambitious progressive vision with sound policy and political realism.
