1. A detection system comprising: an analog to digital converter that converts one or more analog signals into one or more digital samples; a filter that analyzes at least a portion of the one or more digital samples and identifies energy values across a range of frequencies; a frequency selector that selects a subset of the range of frequencies for analysis according to one or more operational characteristics; and an analyzer that analyzes the subset of the range of frequencies along with threshold values to identify one or more results.