Echo decay per delay. 0 to 1. 1.0 = No decay, 0.0 = total decay (i.e. simple 1 line delay). Default = 0.5.

	// Set the decayRatio on the chorus filter to total decay
	@script RequireComponent(AudioSource)
	@script RequireComponent(AudioEchoFilter)
	function Start() {
		GetComponent(AudioEchoFilter).decayRatio = 0.0;
	}

using UnityEngine;
using System.Collections;

[RequireComponent(typeof(AudioSource))]
[RequireComponent(typeof(AudioEchoFilter))]
public class Example : MonoBehaviour {
    void Start() {
        GetComponent<AudioEchoFilter>().decayRatio = 0.0F;
    }
}

import UnityEngine
import System.Collections

[RequireComponent(typeof(AudioSource))]
[RequireComponent(typeof(AudioEchoFilter))]
public class Example(MonoBehaviour):

	def Start() as void:
		GetComponent[of AudioEchoFilter]().decayRatio = 0.0F