A graphic equalizer is a mode of controlling the dynamics of a sound wave. Most sounds are not simple tones consisting of a single frequency instead; they have many different frequencies all playing at the same time. A graphic equalizer allows the listener to selectively adjust specific frequencies without changing the values of the others. It can be used to eliminate hiss sounds from a recording, make a recording sound fuller or warmer, crank the bass up, and also for many other purposes. Each slider in a graphic equalizer has a filter which only allows certain sounds to pass through. The bass and treble sliders only pass frequencies that are below and above a certain level, respectively. All the sliders in the middle have a range that passes signals through between a certain lower limit and a certain upper one. The sliders are all arranged in a row on the control panel, with the bass sliders being at the left and the treble ones, at the right. Analogue graphic equalizers work by phase shifting the signal to a certain amount which means delaying the signal slightly so that it is out of phase with the original signal. When signals are completely out of phase, they cancel out each other, resulting in no sound being produced. When signals are only partly out of phase, they cancel out each other partially. By altering how much of the signal is cancelled out, the graphic equalizer changes the volume of that same signal. Modern digital graphic equalizers work differently by creating a digital image of the signal and changing the amplitude of the signal digitally. This produces a cleaner signal that has less distortion than in the old style of graphic equalizer.