Loudspeakers are typically specified with nominal impedance, often 8 ohms or 4 ohms, although other values are possible. The actual impedance of a typical loudspeaker can vary widely from this rating. In the exercise we shall examine the impedance of two different permanent magnet-voice coil type transducers with respect to frequency. Devices of this type normally exhibit a resonant peak in the bass end and a gradual rise in magnitude as frequency increases. Typical loudspeaker impedance is not nearly as consistent as simple resistors.