I am trying to build a portable device that takes vocal vibrations (from a piezo mic attached to the throat) and outputs them as tactile vibrations elsewhere (say at the sternum). I've found and built simple circuits for preamps that run off 9V like this one (https://www.instructables.com/id/Make-a-Simple-Audio-Amplifier/?ALLSTEPS) but I'm struggling to work out how I can connect and power a vibrating device (e.g. another piezo mic) for the output.
I guess I will need to include a low pass filter too to prevent the device creating audible output (I just want low frequency tactile vibration).
I've seen a similar project here https://www.instructables.com/id/Representing-audio-through-vibration-with-Arduino/?ALLSTEPS but it's using an arduino and I feel like that's unnecessary for my purposes.
Any ideas really appreciated,