A shell for a hermetic compressor unit, the shell having a top section or dome, and a bottom section, the dome having a unique shape which gives enhanced capacity for absorbing and attenuating structural and fluid transmitted wave energies emanating from the unit at wave frequencies of between 1,000 Hz and 2,000 Hz, while reducing total operating noise of the unit, the dome being formed of sheet metal and having a generally inverted cup-shaped configuration with generally cylindrical sidewalls and a top wall having a central portion surrounded by a peripheral portion, wherein the sidewall taken in a generally axial direction is substantially straight, wherein the central portion of the top constitutes from about 40 to about 90% of the total area of the top and has a generally hemispherical configuration on a mean radius of from about 6.5 to about 10.0 inches as measured from an origin point O.sub.2, and wherein the lower section of said shell has a generally cylindrical sidewall and an outwardly curved bottom wall of a generally hemispherical configuration, the ratio of the radius of curvature of the bottom wall to the diameter of the sidewall being from about 0.4 to about 2.0.