Audio texture describes the fine-grained character of sound. Smooth texture: clean, low-distortion reproduction where individual elements feel polished and refined (high-end ribbon tweeters, Class A amplifiers). Rough/grainy texture: audible distortion artifacts or noise that make the sound feel coarse (poor DACs, excessive compression artifacts).
Texture is particularly noticeable in: string instruments (rosin on bow creates a textured sound), vocal fry and breath, and high-frequency content (cymbals, chimes). High-resolution systems reveal more texture — both the good (musical detail) and the bad (recording flaws).