Resonance effects are among the most intriguing phenomena in physics and engineering. The classical case of a mass-spring oscillator driven at its resonant frequency is one of the earliest examples that students encounter. Perhaps the most commonly depicted method of driving the vibrating system is mechanical. An alternative approach presented in this paper describes an electromagnetic driver that is convenient to use and that provides a frequency resolution of 0.001 Hz. A common mass-spring arrangement suspended vertically with a linear array of permanent magnets located at the bottom of the system is used for illustrating the technique.