We studied the perceptual integration of two complex tones, each sent to both ears and formed by amplitude modulation (AM) of a carrier frequency CF by a sinusoid with modulation frequency MF. One tone always had CF = 1500 Hz and MF = 100 Hz. The other had CFs around 500 Hz and MFs around 100 Hz. Both harmonic and inharmonic partials, produced by AM, were employed. The method involved studying the competition between two organizations: (a) the fusion of the two tones, and (b) the tendency of the higher to be stripped out of the mixture by a competing sequential organization. Fusion was best when the both tones had the same MF, even when the resulting partials did not form part of the same harmonic series. Fusion was enhanced when AM applied to the two tones was in phase. Results relate to the perceptual separation of simultaneous voices and favor a theory in which basilar membrane outputs that are amplitude modulated by the same glottal pulse will be allocated to the same voice.