PURPOSE:To guide a desired brain wave, and to promote the efficiency of learning by shifting slightly a frequency of a sound signal for the puspose of learning and appreciation and giving a voice of a different frequency to the left and the right ears. CONSTITUTION:A low-frequency electric signal (2) from an information source (1) of a voice to be subjected to learning or appreciation is divided into two systems, a frequency of the low-frequency electric signal of one system is increased by a frequency adder (3), a frequency of the lower-frequency electric signal of the other system is decreased by a frequency substracter (4), and a frequency difference of outputs of both of them is set to a frequency of a desired brain wave, converted to a voice by a headphone or a loudspeaker, etc., (6), and transferred to both ears of a listener (7). In such a way, the frequency of the brain wave can be guided to a desired value without executing anything except listening to a voice for the purpose of learning or appreciation, and the efficiency of learning can be promoted.
RELAX CENTRALIZED GUIDING DEVICE, SOUND RECORDING DEVICE, SOUND RECORDING MEDIUM AND BROADCASTING EQUIPMENT