Most of the old temples in India have a large bell at the entrance that one needs to ring before entering the temple. Making temple bells is a whole science. These bells are not made out of ordinary metal, but a whole variety of them, including cadmium, lead, copper, zinc, nickel, chromium and manganese.
The proportion at which each one of them mixed is the real Science behind making a bell. Each of these bells is made to produce such a distinct sound that it can create a harmony between your left and right brains. The moment you ring that bell, it produces sharp but lasting sound vibration which lasts for minimum of seven seconds in echo mode — long enough to touch your seven healing centers (or chakras) in your body.
The Bell, known in Sanskrit as the Ghanta/Ghanti is used in all poojas for invoking the Gods.The ringing of the bell produces what is regarded as an auspicious sound. It produces the sound of “OM” the Universal name of the Lord. Most Mantraas (prayers) and vedic chants start with OM. All auspicious actions begin with OM. It fills the mind with peace, makes it focussed and replete with subtle sounds. The ringing of the bell drowns any irrelevant or inauspicious sound, and pervades the whole atmosphere.This reminds us of all pervasive nature of the supreme (Sarva-vyaapi). Even while performing ‘Aarati’ the bell is rung. It is sometimes accompanied by blowing conch, beating drums, playing cymbals and other musical instruments.
The moment bell rings your brain is emptied of all thoughts. Invariably, you will enter a state of trance where you are very receptive.
The bell works as anti-dote to the chaos of your mind. Before you enter temple it helps you to calm down & prepares you for the spiritual awareness you are going to experience.
Even while doing the ritualistic arati, we ring the bell. It is sometimes accompanied by the auspicious sounds of the conch and other musical instruments. An added significance of ringing the bell, conch and other instruments is that they help drown any inauspicious or irrelevant noises and comments that might disturb or distract the worshippers in their devotional ardour, concentration and inner peace.