Masking sound device

Abstract From the Canadian patent

A masking sound source for a sound masking system has adjustable preset means for adjusting the spectral shape of the sound produced. The source includes a random noise generator for producing white noise and having two incoherent outputs to which two low pass filters having different frequency response characteristics are connected. The filtered noise signals are applied to a potential divider forming a contour control device by which a composite noise signal having the requisite spectral shape is derived. This composite noise signal after appropriate, level adjustment, is applied to an output amplifier.