This presentation will begin with a basic introduction to single-ended versus differential signals. A single-ended signal is unbalanced by definition and is measured by the difference between the signal of interest and a constant reference point, normally ground, which serves as the return path for the signal. A problem can be encountered if an error source is introduced to the single-ended signal. Because the ground reference will be unaffected by the injected error, the error is carried forward through the signal. In a single-ended configuration, any variation introduced to the desired signal will be problematic to remove without involving overly complex cancellation techniques. For this reason, single-ended or unbalanced signals are more prone to noise and interference, such as electro-magnetic coupled interference. Also, as will be shown later, unbalanced configurations have higher distortion than balanced circuits.