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This novel amplifier/loudspeaker system combines a traditional and parametric loudspeaker. In this design, the audio input signal is first separated into two frequency bands: low frequency (<800 Hz) and high frequency (>800 Hz) by low pass filters and high pass filters respectively. The traditional loudspeaker generates the audio signal whose frequency is below the 800 Hz threshold while the parametric loudspeaker generates the audio signals above this threshold. The traditional speaker is used to generate most of the low frequency components of vowels while the parametric speaker generates higher frequency components of vowels and the full spectrum of consonants. In this way, bystanders can only hear audio sounds below a threshold frequency and the intelligibility of the overheard audio signal is significantly impaired while the user of the smart device, who is in the private audio zone, would hear the unfiltered audio spectrum.