Delay effects (also known as echo) are a great way of adding interest and a sense of space to your vocals. They come in a range of formats such as dedicated hardware units, pedals and computer plug-ins, and in a wide a variety of different sounding effect styles.
1. Slap Back Delay
Also referred to as slap back echo, slap back delays were particularly popular amongst singers in the 1950s; you will hear its use on many records by artists such as Elvis Presley, Johnny Cash or Eddie Cochran. It consists of a short delay (typically around 60-120 ms) with a single repeat and is generally used as an obvious effect to add interest and enlarge the sound of vocals.
2. Analogue Delay
Analogue delays were typically based around tape machines that were designed to allow the user control over the motor in order to adjust the repeat time. Some machines also included multiple “taps” (playback heads) to make it possible to have delays at varying rhythmic intervals; this allowed musicians to create new sounds that were not possible with natural echoes. The use of tape and sometimes tubes in the design of these machines adds a useful coloration and “warming” to the sound of the delays still desired by artists to this day.
3. Digital Delay
Digital delays use a computer chip to generate delay/echo effects. When compared to tape-based delay machines, these have the advantage of easier controls, greater reliability and reduced cost. Digital delays also often include extra functions that would not be easy to achieve with tape delays such as controllable modulation effects and tempo matched delays. Many digital delays also offer stereo operation, enabling the user to vary the pan of the echo repeats and create effects such as a “ping-pong” delay whereby the repeats alternate between the left and right sides of the stereo field.
As the memory increased in digital delay machines in the 1980s it became possible to use the repeating ability of a delay machine to capture longer recordings that could be infinity repeated to create a loop. Since then manufacturers have made devices specifically designed for this task and offer extra functions such as overdubs and greater control over the loops; as such these days they are closer to multi-track recorders than the delay machines of the 1980s.
5. Delay Throws
Delay throws are a momentary delay effect that is switched on for a particular word, syllable, or phrase in a song. You will often find them used in Pop music as a tool for creating interest in the mix at the end of a vocal line or to add impact to a particular word of importance. In the studio they can be automated within your DAW software, however there are also various delay effect units designed for live use that also enable you to switch on and off delays at particular moments within a song.