Damper pedal and decay settings govern sympathetic vibration and note fade time

Evidence

Damper resonance. Varies the amount of sympathetic vibration between strings when the damper pedal is down. … Decay time. Changes the time it takes for notes to decay. … Damping time. Adjusts how long it takes notes to fade out with the damper pedal depressed. — Eric J. Heller, Why You Hear What You Hear- An…, 1852