The respiratory booster machine is configured to generate and transmit particularly designed and timely delivered vibrations to the lungs of a subject to improve ventilation, augment diffusion of gases across alveolar membrane, facilitate pulmonary blood perfusion, prevent focal alveolar collapse, and enhance effective expectoration. The machine has an acoustic signal generator having modulated wave-generating circuitry and an acoustic signal transmitter having an electro-acoustic transducer. Vibrations from the acoustic signal are induced into the subject's air stream, in one embodiment by a specially designed tube system, and then transmitted to a subject's airways via any type of endotracheal tube, respiratory mask, nasal prong, or directly through the chest wall. Acoustic signal receivers connected to a computer receive and analyze the effect of the vibrations on the subject. The machine can be used independently or in combination and cooperatively with any type of ventilator machine, either conventional or high frequency.