I'm creating something as a side-project, but I've encountered a problem in a field I'm not well-versed in. There is a material I am looking to excite with a resonance frequency of 50 Hz. I need the smallest possible device to create the largest amount of vibration, I've looked into some small sound emitters (a few centimeters/inches) but I'm concerned that they won't make large enough vibrations (again, I don't know much about this). Something that could be incorporated into a circuit would be fantastic. Price is not a concern. Does anybody know of any devices or ideas that would satisfy my needs?