Systems and methods for improved NMR signal detection are described. The system receives NMR signal data produced by a sample over time in response to an excitation pulse and selects a predefined system function for application to the NMR signal data for systematic variation of signal properties The system function has a different influence on NMR signal components than on noise components of the sampled signal and has a variation parameter to control the systematic variation. A plurality of variation parameter values is provided with differing values to influence broad NMR signals as well as weak NMR signals. The system generates for each variation parameter value a corresponding intermediate data set by applying the system function with the respective variation parameter value to the NMR signal data. Further, from each intermediate data set, a respective base value centered spectrum is generated in the frequency-domain.