A channel equalizer arranged to receive a data signal encoded by a plurality of amplitude levels, the circuitry including a filter having a plurality of taps, each tap generating an output signal based on a coefficient, an input for receiving an error signal for adapting the coefficients, and an output for outputting a filtered signal; and blind error generation circuitry arranged to generate the error signal, the blind error generation circuitry including: error estimating circuitry arranged to estimate the error of the filtered signal based on maximum likelihood; and adding circuitry coupled to the error estimating circuitry and to the output of the filter and arranged to add at least part of the filtered signal to the error estimated by the error estimating circuitry to generate the error signal.