Patent Document ID: 9640193
Application ID: 14355458

Base Claim:
1. A method for frequency-lowering of audio signals for improved speech perception, comprising: receiving, by an analysis module of a device, a first audio signal; detecting, by the analysis module, one or more spectral characteristics of the first audio signal, the detected one or more spectral characteristics corresponding to one or more respective non-sonorant sounds; classifying, by the analysis module, the one or more respective non-sonorant sounds, based on the detected one or more spectral characteristics of the first audio signal; selecting, by a synthesis module of the device, a second audio signal from a plurality of audio signals, responsive to at least the classification of the one or more respective non-sonorant sounds; and combining, by the synthesis module of the device, at least a portion of the first audio signal with the second audio signal for output to form a combined audio signal with frequency characteristics audible to the user.

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Claim 6:
6. The method of claim 1 further comprising: classifying the one or more non-sonorant sounds in the first audio signal as belonging to a second group of one of a predetermined plurality of groups having distinct spectral characteristics, based on a spectral slope of the first audio signal exceeding a threshold and a spectral peak location of the first audio signal not exceeding a second threshold.