Depending on the tone, key or frequency they may use these for applying sound healing to a particular part of the body for healing. They might also use a different singing bowl for each of the different chakras.
Selecting a sound healing instrument will very much depend on what the therapist / practitioner / healer is looking for or is guided to purchase. Generally speaking the larger the instrument, the bigger, louder and deeper the sound, and also the more resonance it will create.
Also in selecting a sound healing instrument such as a gong or Tibetan singing bowl, you are likely to pay more for a better quality instrument. By this I mean that it is important to check out an instrument before purchasing, and to listen to the sound it creates and how much sustain the instrument might have. By ‘sustain’ I mean how long the note from the instrument continues after it is tapped or after you have stopped rubbing its edges. A longer sustain invariably means a better quality instrument.
Intuition
More importantly allow yourself to be guided by your intuition when choosing a sound healing instrument. When you tap a gong or a bowl you can immediately sense if you can feel a connection with that instrument. It is the same if you are buying a guitar or violin or any instrument. Firstly you must feel a connection with that particular instrument. If it doesn’t intuitively feel like the correct instrument to purchase, it’s not likely to resonate with you in a way that will allow you and the sound you create to connect and resonate with your client.