One might think that Naada simply means sound. But the word has deeper meanings. Translating it plainly as ‘sound’ does not capture the true meaning and essence of it. Sangeeta Ratnakara, a book written in 13th century India, defines Naada in the following way:
नकारं प्रांणमामानं दकारमनलं बिंदु:।
जात: प्राणअग्नि संयोगातेनम नदोभिधीयते ।।
The sanskrit word Naada is formed from two root words: Na and Da.
Na kaara or Na is Praana Vaachak- it signifies the ‘breath of life’.
Da kaara or Da is Agni Vaachak- it signifies the fire element.
The union of this ‘breath of life’ and ‘fire’ gives birth to Naada.
आहोतीनहतश्चेती द्विधा नादो निग्ध्य्ते
सोय प्रकाशते पिंडे तस्तात पिंडो भिधियते
According to the above shloka, there are two types of Naada: 1. Aahatha Naada and 2. Anaahatha Naada. The aahatha and anaahatha naadas manifest in material existences; they are present in the body too.
1. Aahatha Naada: The sound that we hear when two particle collide; the sound we are accustomed to hearing dayin and day out- that is called the Aahata Naada. The chirping of a bird, the loud honking of a lorry, the sound of the slow flow of a river, the voice of your speech or your child’s- it could be music to your ears or noise, but all of this is Aahatha Naada: the sound that we hear with our ears.
2. Anaahatha Naada: This is the sound that exists everywhere, even now- it is there around you and I. But you can’t hear it with your ears. This is the sound that only the sages and siddhas can hear. The sound has no source or beginning, yet it exists- it is swayambhoo- self born. This all pervasive Anaahatha Naada, which is still out of reach to the current boundaries of scientific research can be experienced through spirituality.