A data acquisition system and method are described that may be used with various spectrometers. The data acquisition system may include an ion detector, an initial/transient processing module, and a spectra processing module. The initial/transient processing module is provided for processing the ion detection signals and for supplying processed signals to the spectra processing module. The transient processing module may contiguously sample the ion detection signals at a rate of at least 1.5 GHz. The spectra processing module may generate spectra from the transients at a rate of at least 50 spectra per second. The initial processing module may be configured to have a sensitivity that is sufficient to detect a single ion received within one of over at least 100 transients and to detect and quantify a number of ions simultaneously striking said ion detector up to at least 10 simultaneously striking ions.