An apparatus comprising a slicer configured to produce a symbol decision value and a symbol error value utilizing, at least in part, a slicer input signal; and an automatic gain controller configured to facilitate the automatic control of a gain applied to the slicer input signal by producing a gain control signal, the automatic gain controller comprising a decision-directed amplitude error detector configured to utilize, at least in part, the symbol decision value and the symbol error value to produce an amplitude error signal, and a loop filter configured to utilize the amplitude error signal to produce the gain control signal.