Spectral peak sharpness is bounded by the duration of echoes

Evidence

The wedge echoes cease of their own accord, never to return. The power spectrum therefore has peaks no sharper than Δf = 1/τ, where τ is the time of the last echo; τ ≈ 7.9/35 = 0.225, so Δ f ≈ 4.5, which agrees with the peak widths seen in figure 12.4. — Eric J. Heller, Why You Hear What You Hear- An…, 1138

Categorization

• QUESTION: Worth chasing: does the Δf = 1/τ bound explain audible differences between small reflective rooms and open spaces?