An impulse response is itself an autocorrelation of the system

Evidence

Here, we take an active perspective, focusing attention to the power supplied by a drive, adding a new physical context to the Wiener-Khinchin theorem. The key point is that the response to a sudden kick—the impulse velocity response—is a ready-made autocorrelation. The spectrum derived from it is the power actually delivered by a sinusoidal drive acting on the system, at the point of the kick. — Eric J. Heller, Why You Hear What You Hear- An…, 1065

Categorization

• DEFINE: Explains how the Wiener-Khinchin theorem gains new physical meaning under an active drive perspective.