Comparison of 440 Hz vs. 432 Hz Tuning through EEG of Human Brain Waves*

440 Hz is the standard pitch of the musical note A4 above middle C, which was adopted for the tuning of musical instruments by the International Organization of Standardization (ISO) in 1955 and reaffirmed in 1975. On the other hand, there is a recent movement of returning the music tuning to A4=432 Hz, a scientific pitch that leads to middle C being at 256 Hz, the eighth power of 2. Many music uploads tuned at 432 Hz on YouTube.com are claimed to render relaxation and healing for the brain. There was even better audience response reported for music performances tuned to 432 Hz.

In this investigation, we collected human brain waves (including alpha, beta, delta and theta waves) upon external sound stimuli tuned at 440 Hz and 432 Hz, with a BIOPAC system through the EEG (electroencephalogram) setup. EEG is the recording of the brain’s activity through electrodes placed on the scalp in detection of the collective electrical activity from thousands of neurons right beneath. The EEG data collected from the human subjects will be analyzed for evaluation and comparison of the effects of sounds tuned at 440 Hz vs. 432 Hz on human brain waves.