According to one embodiment, a system for processing data includes a processor and logic integrated with and/or executable by the processor, the logic being configured to read data from a magnetic data storage medium using a read channel, detect and track positive peak amplitudes and negative peak amplitudes of a readback waveform during the data reading using a tracking threshold module, and perform asymmetry compensation on the data using an asymmetry compensator based on input from the tracking threshold module in an asymmetry compensation loop, wherein the asymmetry compensator does not rely on an input from path metrics in order to perform the asymmetry compensation. Other systems, such as magnetic tape drives, and methods for processing data, and specifically for asynchronously providing asymmetry compensation for data read from a magnetic tape, are described in more embodiments.