The performance of a higher-order single-stage sigma-delta modulator (/spl Sigma//spl Delta/M) is determined by the loop filter in which the quantizer is embedded. Not the coefficients in the loop filter themselves, but ratios of them determine the input-output relationship in the modulator and thus its performance. The ratios of coefficients that affect the performance of the /spl Sigma//spl Delta/M are found, thus establishing a search space for optimization of the modulators. An optimization method of the random search type is presented and used for optimizing the /spl Sigma//spl Delta/M to any particular input.