An improved form of spectrograph utilizing a contour representation of amplitude is described. Detailed consideration is given to the novel features incorporated in the instrument such as variable sample length, fully adjustable frequency‐scan limits, and a quasistationary display. The use of contours to extend the dynamic range of the display medium is described, together with a versatile digital technique for obtaining any practical amplitude contour spacing. Finally, samples of typical plots are shown, indicating the versatility and wide application of the spectral contour plotter to acoustical signal analysis.