title: Understanding speech when wearing communication headsets and hearing protectors with subband processing.
abstract: An adaptive, delayless, subband feed-forward control structure is employed to improve the speech signal-to-noise ratio (SNR) in the communication channel of a circumaural headset/hearing protector (HPD) from 90 Hz to 11.3 kHz, and to provide active noise control (ANC) from 50 to 800 Hz to complement the passive attenuation of the HPD. The task involves optimizing the speech SNR for each communication channel subband, subject to limiting the maximum sound level at the ear, maintaining a speech SNR preferred by users, and reducing large inter-band gain differences to improve speech quality. The performance of a proof-of-concept device has been evaluated in a pseudo-diffuse sound field when worn by human subjects under conditions of environmental noise and speech that do not pose a risk to hearing, and by simulation for other conditions. For the environmental noises employed in this study, subband speech SNR control combined with subband ANC produced greater improvement in word scores than subband ANC alone, and improved the consistency of word scores across subjects. The simulation employed a subject-specific linear model, and predicted that word scores are maintained in excess of 90% for sound levels outside the HPD of up to ∼115 dBA.
authors.affiliation: Ergonomic Technology Center, University of Connecticut Health Center, Farmington Avenue, Farmington, Connecticut 06030-2017.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Brammer
authors.affiliation: Ergonomic Technology Center, University of Connecticut Health Center, Farmington Avenue, Farmington, Connecticut 06030-2017.
authors.forename: Gongqiang
authors.initials: G
authors.lastname: Yu
authors.affiliation: Ergonomic Technology Center, University of Connecticut Health Center, Farmington Avenue, Farmington, Connecticut 06030-2017.
authors.forename: Eric R
authors.initials: ER
authors.lastname: Bernstein
authors.affiliation: Ergonomic Technology Center, University of Connecticut Health Center, Farmington Avenue, Farmington, Connecticut 06030-2017.
authors.forename: Martin G
authors.initials: MG
authors.lastname: Cherniack
authors.affiliation: Ergonomic Technology Center, University of Connecticut Health Center, Farmington Avenue, Farmington, Connecticut 06030-2017.
authors.forename: Donald R
authors.initials: DR
authors.lastname: Peterson
authors.affiliation: Department of Communication Sciences, University of Connecticut, Storrs, Connecticut 06269.
authors.forename: Jennifer B
authors.initials: JB
authors.lastname: Tufts
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000465:Algorithms; D000669:Amplifiers, Electronic; D032882:Comprehension; D003198:Computer Simulation; D004430:Ear Protective Devices; D004867:Equipment Design; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D009622:Noise / Q000009:adverse effects; D010470:Perceptual Masking; D011571:Psychoacoustics; D021641:Recognition, Psychology; D012815:Signal Processing, Computer-Assisted; D059629:Signal-To-Noise Ratio; D013018:Sound Spectrography; D013061:Speech Acoustics; D013065:Speech Intelligibility; D013067:Speech Perception; D014159:Transducers; D055815:Young Adult