Ear training is the process of connecting music theory (notes, intervals, chords, scales, melodies, etc.) with the sounds we hear. In other words, studying ear training is building a bridge between the language of music and the sounds that are designated by that language.
The more we train our ear to recognize this connection, the better we get at playing music & understanding it. Needless to say, it activates inner parts of brain which perhaps you never used.

We have created soundscapes for each Fundamental Notes which can be run in loop for exposing ears to those frequencies and its harmonics. From the experts, its always best to associate a color with each note for utilizing associative memory of brain and easy recall.