One of the many different ways in which the sound produced by an electric guitar can be influenced is through the use of various time based effects. Typically a player will use a pedal, operated by foot, which will affect the sound of the guitar once pressed or rocked. These time based effect pedals work by producing a copy of the sound made by the guitar, and then plays back this copy either once, a fraction of a second after the original has been played, or by playing back the copy several times, each decreasing slightly in volume. The first of these effects - playing the copy just once, very quickly after the original sound, produces a kind of 'slap' sound. The second time based effect, playing the copy several times decreasing in volume creates the impression of an echo - a very popular effect used quite widely.



Despite being electric guitars, there are two ways in which the sound can be affected through such time based delay effects, analogue and digital. The digital systems will be able to produce a much more accurate and precise quality of sound, and be considerably more flexible when it comes to affecting exactly how you wish the sound to be produced. The exact delay, the number of repetitions, the decay in volume, and several other aspects of the sound can all be minutely affected by the use of digital controls.

However, there are many players who prefer the analogue systems, despite their slightly less versatile nature. The reason, so they argue, is that the sound produced by an analogue time based effect system is much warmer. If you are considering purchasing a time based effect system, and are not sure whether to go for a digital or an analogue system, you may well feel that the best way of helping to choose is by listening to the quality of sound. This, as with so many other aspects of the instrument, is the best way to judge which guitar or accessory is going to be right for you. As far as ease of control is concerned, there is relatively little to pick between the two systems.

Whilst the concept of feedback may give rise to screeching microphones held too close to a speaker, piercing the audience's eardrums, controlled feedback can create a sound that makes the electric guitar seem to warble, and perhaps almost scream, adding emphasis to the note and helping to give the guitar its voice. Feedback in this way needs to be very controlled, and time based effects gadgets and accessories can help to create this particular sound. This is achieved by having a tracking oscillator circuit built in to the unit, and it is this circuit which holds on to a particular note, amplifies it significantly, and then transmits this amplified note back in to the input side of the sound system.

This is a little like holding the microphone close to the speaker, or even like holding a video camera close to the image being produced by the camera on a television screen. By sending the output signal back in to the input part of the system, feedback is generated. In the case of the time based effect created with the electric guitar, this is coupled with the amplification to create a distinctive roar.