I read from their official Q&A
link Official Sapienmed FAQ (Updated)
here is what it said:
4. Do you need to hear the fields in order for them to work? (for example playing a field on the lowest possible volume in ur pocket all day without being able to hear anything)
Summary
No. So as long as they are playing and the audio is playing from somewhere around you very close, the energy will be streaming onto your being. Would it affect other people around you? Environmental fields yes. Other fields that work more on a personal level may likely be rejected by other people’s subconscious minds since they didn’t agree to have sun free tanning energy on their being. It is still possible that they do though. Depends on the proximity though. They can’t quite reject an environmental fields because the fields affect the environment directly and the environment indirectly affects everyone in it.