Abstract: An exemplary method for selecting data density values (e.g., bits per inch) and track density values (e.g., tracks per inch) for magnetic recording media having variable bit aspect ratios comprises obtaining a plurality of data density values and a plurality of track density values as a function of a corresponding plurality of bit error rates; determining a data density/track density correlation between the plurality of data density values and the plurality of track density values for at least one Sector Error Rate; and determining a data density capability value and a track density capability value that provides an areal density capability value that satisfies one or more predefined criteria (e.g., a substantially maximum areal density capability value) using the data density/track density correlation.

Abstract: Methods including determining a distribution of a position error signal (PES) of a magnetoresistive head by obtaining PES data from a servo controller associated with the magnetoresistive head; determining an encroachment function of a storage disc; and determining a track density of the storage disc by considering both the PES distribution and the encroachment function.