Hi Bob - the frequencies being played are at and around 110 Hz (A2), so you'll need a set of speakers which can play down to that frequency. Any set of speakers or headphones setup to play back music will achieve that. If you are playing out of a mobile device then it probably won't be able to play back those frequencies unless you use headphones.
You cant hear anything except your voice.
Hi Bob - the frequencies being played are at and around 110 Hz (A2), so you'll need a set of speakers which can play down to that frequency. Any set of speakers or headphones setup to play back music will achieve that. If you are playing out of a mobile device then it probably won't be able to play back those frequencies unless you use headphones.