About vibrational sound healing, different people have their own feeling.
In quantum physics everything is just energy at its smallest level, our consiousness is projected to us with ourselves working as a reciever of a divine frequency within the pineal as symbolized in various manmade religions as the pinecone.
Negative and Positive vibrations of our actions and intentions coincide with the idea of karma, time being circular by nature and only linear by human perception and logically explained as cause and effect.
In my opinion, singing Bowls work to stimulate, balance and purify your senses, pineal frequency and chakras by sending off neutral vibrations to flush your auric field along with any negative vibrations that are stealing your clarity of thought.
The tone working as a form of mental reboot to still you in the moment so you can examine your thoughts and discover your inner self through focused intention and practice.
Just as all things are energy that are of this world, so are thoughts and beliefs, the heart gives off its own vibrations with disregard to your worldy perceptions. This is why you always hear so much about positive perception of life being advertised and spoke about, its symbolic to the true nature of existence and how you find your truth.