A measurement systems that reduces spurious artifacts in reflected signals by generating and employing an improved maximum length sequence. Accurate acoustic measurements with both high SNR and low spurious artifacts are made possible by generating Wide MLS (WMLS) which modifies a base MLS by replacing each value with a sequence that includes the value and one or more additional values, where typically the replaced values have opposing polarities and, the additional signals have intermediate values. An exemplary intermediate values can be approximately zero value.