A signal processing evaluator and methods that compare a digital waveform of a cardiac signal to a first processed signal generated by a test system such as an EP recorder or an EP mapping system and generates a first finding evaluating how well the test system filters non-cardiac signals or simulated body impedance. A simulator and methods that send cardiac signals including non-cardiac signals or simulated body impedance to a test system and to a signal processing evaluator for evaluation of the test system.