Along with reverb, delay is a natural part of sound that bounces around a room. When you speak (or sing or play) in a room, you often hear not only reverb but also a distinct echo. This echo may be short or long depending on the size of the room. The original sound may bounce back to you as a single echo or as multiple, progressively quieter delays.

Several types of delay effects exist, including a slap-back echo, tape delay, and multiple delays, and each of them is designed to add dimension to your instrument. To create these various effects, you adjust several parameters, as the following list and the following illustration makes clear.

Different delay processors have different parameters, but the three most universal and useful parameters are time, feedback, and mix/effect level, as follows:

A delay effect processor allows you to create various echoes.
A delay effect processor allows you to create various echoes.

  • Gain: This lets you set the signal level going into the delay.

  • Mix: This parameter controls the output level of the effect. The higher you set this parameter, the louder the delayed signal is relative to the original signal.

  • LPF: The low-pass filter (LPF) lets you filter out some of the high frequencies from the delay.

  • Delay: This parameter controls the amount of time between the initial signal and the repeated sound. The time is listed in milliseconds (ms) and can be as short as a few milliseconds or as long as several seconds.

  • Depth: This parameter lets you add modulation to the delay so that you can create a chorus effect. The higher the level on this setting, the greater the modulation.

  • Rate: This setting lets you adjust the amount of time that the modulation takes to go one time through its cycle.

  • Feedback: The Feedback parameter controls how many times the echo repeats. A low setting makes the echo happen just once, and higher settings produce more echoes.