Many different components can be altered to change the user's perception of the sound, and in turn, their perception of the underlying information being portrayed. Often, an increase or decrease in some level in this information is indicated by an increase or decrease in pitch, amplitude or tempo, but could also be indicated by varying other less commonly used components. For example, a stock market price could be portrayed by rising pitch as the stock price rose, and lowering pitch as it fell. To allow the user to determine that more than one stock was being portrayed, different timbres or brightnesses might be used for the different stocks, or they may be played to the user from different points in space, for example, through different sides of their headphones.