The present disclosure includes apparatus, systems, and techniques relating to noise-predictive detector adaptation. A described technique includes operating a decoder to decode a received encoded signal based on estimation parameters to produce paths including a first path and a second path, the second path being an alternate to the first path, determining a decoded path based on at least a portion of the paths, determining a winning path of the first path and the second path based on whether the decoded path matches the first path or the second path, and updating the estimation parameters based on one or more error terms and the winning path to favor selection of the winning path by the decoder and to disfavor selection of a losing path of the first and second paths by the decoder in a subsequent iteration.