Of much less concern, yet still important especially in audio applications, is the microphonic or piezoelectric effect. Barium titanate, which is the base ceramic material for most dielectric systems, will exhibit microphonic effects, while tantalum capacitors exhibit no microphonic effects. An internal experiment involved the opposite phenomena, whereby the part was shaken while under bias and the resulting generated voltage was measured. It was performed on a series of 1µF devices. While this experiment does not give an empirical number, the resulting relative voltage generation tells the story. This experiment confirms that the higher the K of the ceramic capacitor, the worse the microphonic effect becomes.