Reproducing the Cocktail Party Effect
James F. Kaiser, Edward E. David · The Journal of the Acoustical Society of America · 1960
The Cocktail Party Effect allows the binaural listener to concentrate on speech from one talker, suppressing others in his environment. As contrasted to the monaural listener, the binaural auditor gains between 5 and 15 db signal-to-noise ratio necessary for 50% intelligibility. A gain of this magnitude cannot be reconciled with linear array theory which prescribes addition of the two available aural inputs. An alternative accounting can be made by postulating signal processing based upon properties of binaural hearing. In this modal the binaural processor derives a temporary signal which is used to gate the aural input. In effect, the gating signal leaves the major portions of the preferred talker's speech envelope intact while suppressing sound from other talkers or background noise when these do not overlap with the preferred speech. A preliminary circuit version of such a processor which derives the gating signal by cross correlation has been built and tested. Subjective measurements in two- and three-speaker environments yielded increases of 9 and 5 db, respectively, in signal-to-noise ratio.