초록 ▼

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 in which two low pass filters having different frequency resp

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 in 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.

대표청구항 ▼

A masking sound source for a sound masking system comprising a random noise generating circuit having at least two incoherent outputs, first and second low pass filters having different frequency response characteristics each connected to a respective one of said outputs for deriving a noise signal

A masking sound source for a sound masking system comprising a random noise generating circuit having at least two incoherent outputs, first and second low pass filters having different frequency response characteristics each connected to a respective one of said outputs for deriving a noise signal having a predetermined spectral shape within the audio frequency range, continuously adjustable contour control means connected to the filters for deriving from said noise signals a composite noise signal having a spectral shape corresponding to the setting of the continuously adjustable contour control means, and an impedance transformer having an input coupled to said contour control means to receive the composite noise signal, and having an output circuit, and power amplification means having an input circuit coupled to the output circuit of the impedance transformer and an output circuit providing terminals for connection to a loudspeaker.