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Introduction In noisy social gatherings, listeners perceptually integrate sounds originating from one persons voice (e.g., fundamental frequency (f0) and harmonics) at a particular location and segregate these from concurrent sounds of other talkers.Though increasing either the spectral (e.g., f0) or the spatial distance between talkers promotes speech segregation, the synergetic effect of having more than one cue available is less well understood.Methods We studied how spectral and/or spatial distances between 2 simultaneously presented steady-state vowels contribute to participants perception (accuracy of both vowels) and activation in auditory cortex using magnetoencephalography (MEG).Results Participants were more accurate in identifying both vowels when they differed in f0 and location than when they differed in a single cue only or when they shared the same f0 and location.The combined effect of f0 and location differences closely matched the sum of single effects.The improvement in concurrent vowel identification coincided with an object-related negativity (ORN) that peaked at about 140 ms after vowel onset.The combined effect of f0 and location on dipole source waveforms closely matched the sum of single effects even though vowels with different f0, location, or both, generated different time courses of neuromagnetic activity.The model-free beamforming analysis provided converging evidence for summation of f0 and location cues in auditory cortices during speech segregation.Conclusions We propose that during auditory scene analysis, acoustic differences among the various sources are combined linearly to increase the perceptual distance between the cooccurring sound objects.