Any set of higher HARMONICs or PARTIALs in a SPECTRUM which cannot be individually identified because they activate a common area of the BASILAR MEMBRANE which is less than that corresponding to the CRITICAL BANDWIDTH.

In terms of FOURIER ANALYSIS, it is the part of a COMPLEX TONE whose Fourier components cannot be individually heard. The residue has an important role in the perception and recognition of TIMBRE. Therefore, HEARING LOSS in the upper frequency region (as in PRESBYCUSIS) decreases the accuracy of such perception. Compare: TRANSIENT.

If the components of the residue are harmonic, the PITCH ascribed to the spectrum will be that of the residue tone or missing fundamental (see FUNDAMENTAL for further discussion).

Ref.: J.F. Schouten, "The Residue: A New Component in Subjective Sound Analysis," Proceedings, Koninklijke Nederlandsche Akademie van Wetenschappen, 43, 3:356-365; Schouten et al., "Pitch of the Residue," Journal of the Acoustical Society of America, 34, 8 (part 2), pp.1418-24.