With Rainbow you find the best Spectral Estimation Method for a Power Spectral Density plot. A menu of 10+ spectral estimators from Steve Ka\'s textbook, Modern Spectral Estimation, 1988, is available to choose from. The results differ dramatically from one estimator to another. Plus, varying input parameter and/or number of points may provide discrepancies. See how zero padding effects your results.This program is an application designed to allow the calculation of spectral estimations.Some estimators can detect signals 50 to 100 dB from main signal. The unwritten rule of \'30 dB is okay\' (i.e. hidden) is no longer true.Here are some key features of \"Rainbow\":