Refraction of sound ray

sound density

Sound Ray

sound ray curve

sound ray tracking plotter

sound-ray diagram

The propagation path of sound ray

gamma ray (=γ-ray)

gamma ray density meter

gamma-ray density meter

ray density

ray-density normalization

γ-ray density gauge

γ-ray density meter

X-ray density

a sound mind in a sound body

infra-audible sound (=infrasonic sound)

rate of sound and attenuation of sound

sound absorption-sound insulation-vibration isolation technology