1. A method for modeling a secondary path for an active noise control system, comprising: receiving a reference signal; filtering the reference signal with an initial secondary path model to obtain a filtered reference signal; calculating an autocorrelation matrix from the filtered reference signal; calculating a plurality of eigenvalues from the autocorrelation matrix; calculating a maximum difference between the plurality of eigenvalues; iterating a test model to determine an optimized secondary path model having a plurality of optimized eigenvalues that have a minimized difference that is less than the maximum difference of the plurality of eigenvalues, wherein the optimized secondary path model may be utilized in the active noise control system.