title: Spectral density affects the intelligibility of tone-vocoded speech: Implications for cochlear implant simulations.
abstract: For small numbers of channels, tone vocoders using low envelope cutoff frequencies are less intelligible than noise vocoders, even though the noise carriers introduce random fluctuations into the crucial envelope information. Here it is shown that using tone carriers with a denser spectrum improves performance considerably over typical tone vocoders, at least equaling, and often surpassing, the performance possible with noise vocoders. In short, the spectral sparseness of tone vocoded sounds for low channel numbers, separate from the degradations introduced by using only a small number of channels, is an important limitation on the intelligibility of tone-vocoded speech.
authors.affiliation: Speech, Hearing and Phonetic Sciences, University College London, Chandler House, 2 Wakefield Street, London WC1N 1PF, United Kingdom stuart@phon.ucl.ac.uk, yue.zhang.12@ucl.ac.uk, k.speers.12@ucl.ac.uk.
authors.forename: Stuart
authors.initials: S
authors.lastname: Rosen
authors.affiliation: Speech, Hearing and Phonetic Sciences, University College London, Chandler House, 2 Wakefield Street, London WC1N 1PF, United Kingdom stuart@phon.ucl.ac.uk, yue.zhang.12@ucl.ac.uk, k.speers.12@ucl.ac.uk.
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Speech, Hearing and Phonetic Sciences, University College London, Chandler House, 2 Wakefield Street, London WC1N 1PF, United Kingdom stuart@phon.ucl.ac.uk, yue.zhang.12@ucl.ac.uk, k.speers.12@ucl.ac.uk.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Speers
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000162:Acoustics; D001302:Audiometry, Speech; D019929:Cochlear Implantation / Q000295:instrumentation*; D003054:Cochlear Implants; D006801:Humans; D009622:Noise / Q000009:adverse effects*; D010470:Perceptual Masking; D019986:Persons with Hearing Disabilities / Q000523:psychology / Q000534:rehabilitation*; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013065:Speech Intelligibility; D013067:Speech Perception