Purpose: The effects of multichannel expansion on the objective and subjective evaluation of 20 listeners fitted binaurally with 4-channel, digital in-the-ear hearing instruments were investigated. Method: Objective evaluations were conducted in quiet using the Connected Speech Test (CST) and in noise using the Hearing in Noise Test (HINT) at 40,…

The effectiveness of routine daily hearing and monitoring of 44 students' aids was evaluated using detailed visual-auditory inspection and electroacoustic analysis. Results indicated the need for such changes as a periodic electroacoustic analysis of all hearing aids. Followup revealed a significant decrease in incidence of hearing aid…

Input-output (I/O) functions of hearing aids were measured in response to a 2000 Hz tone burst, having 0.5 ms rise/fall time and 10 ms duration. Findings indicated that the steady-state output limitation characteristics of hearing aids cannot be estimated from their onset responses. (Author/DB)

Fifty-five adults with sensorineural hearing impairments participated in the study which indicated nonsignificant interaid performance differences among electroacoustically homogeneous aids. Among other conclusions were that the comparative hearing aid evaluation will not be a good predictor of success in daily communication unless relatively…

Investigation of the effects of frequency range, harmonic distortion, intermodulation distortion, and transient response of hearing aids upon judgments of quality showed transient response measurements the best predictor of listener judgments, with voice a possible factor. (Author/KW)

An implantable type hearing aid was tested to determine its ability to produce cochlear potentials in guinea pigs. (Author)

Speech recognition threshold (SRT) was measured in quiet and in noise for normal hearing subjects and subjects with high frequency sensorineural hearing loss. The speed, reliability, and apparent sensitivity of the SRT to frequency response characteristics make it a potentially useful tool for hearing aid evaluation. (Author/DB)

Speech intelligibility scores obtained with unilaterally hearing impaired subjects under aided and unaided experimental listening conditions suggest that, while the CROS (Contralateral Routing of Signals) hearing aid enhances intelligibility under favorable use conditions, it degrades speech intelligibility in some demanding situations. (Author/KW)

Three hearing aid manufacturers provided custom full-shell in-the-ear hearing aids designed for maximum acoustic gain for each of three hearing-impaired adults. Full-on coupler gain curves were similar across all nine hearing aids, with individual differences producing substantial variance in insertion gain across hearing aids. (Author/DB)