The raga is said to be the soul of Hindustani music. Each raga in Hindustani music is associated with particular or a variety of emotional experiences. In this paper, we took a neurocognitive physics approach to quantitatively evaluate the emotions induced by two sets of Hindustani raga music. The study reports the change in the complexity of EEG brain rhythms while they listen to Hindustani music (instrumental) of contrast emotions. The two set of raga clips chosen for our analysis are Chayanat (romantic/joy) and Darbari Kannada (sad/ pathos) on the first day while Bahar (romantic/joy) and Mian ki Malhar (sad/ pathos) on the second day. 20 subjects voluntarily participated in the EEG study, who were made to listen to 2 min ‘alaap’ section of each raga. Detrended fluctuation analysis (DFA) was used to determine the complexity of neuronal oscillations in 5 electrodes, when the subjects listened to clips of contrast emotions. Alpha and theta brain rhythms were extracted from each of these electrodes and power spectral density (PSD) evaluated to estimate the alpha and theta power in all these electrodes. The results show that the complexity of brain rhythm varies significantly when the emotion of music changes from happy to sad.