Binaural hearing is an important phenomenon in hearing for human being. Nowadays, the role of binaural hearing in the process of amplification has been focused. Since hearing aids act separately in the process of amplification and hearing, the attentions has been devoted to designing a system for binaural amplification by means of Beam forming which will be explained in more details in the current article.

Objective: Comparing analog and digital hearing aids reducing disability caused by hearing deficiency among moderate to severe sensorineural hearing-impaired persons.
Method and Material: This descriptive-analytic study was carried out on two groups of subjects participated in this study in some audiology clinics of hearing aid since May 2002 to October 2003. Twenty subjects wore analog hearing aids and twenty one subjects wore digital hearing aids. In this study , no subject had previous middle ear or psychological problems. APHAB questionnaire was completed before using hearing aid and 2 months after to determine benefit of hearing aid use. Results: Total score mean of APHAB inventory before and after use of analoge hearing aids were 52.215+6.420 and 32.300+3.443 respectively. Also total score mean of APHAB inventory before and after use of digital hearing aids were 54.9252+9.028 and 26.321+10.916 respectively. There was no significant difference between total mean score of APHAB inventory before and after using analog and digital hearing aids (P=0.058).While there was significant difference between total mean score of APHAB questionnaire before and after use of analog hearing aids (P<0.001) and also before and after use of digital hearing aids (P<0.001). Moreover age, gender , litracy level , occupation , degree of hearing loss and manner of hearing aid usage did not have significant effect on APHAB results. Configuration of loss had siginficant effect on aversiveness subscale before and after use of analog hearing aids (P=0.008). Previous experience and duration of hearing aid usage had significant effect on aversiveness subscale before and after use of digital hearing aids (P=0.043) and (P=0.024), respectively , while all of these three items did not have significant effect on total mean score of APHAB inventory and also total mean scores of three subscales of ease of communication , reverberation and background noise.
Conclusion: Comparing to analog hearing aid , digital one is significantly benefitial for reverberation and background noise for hearing-impaired persons , but it has no benefit for ease of communication and aversiveness that may be arised from effects of the individual expectation , psychological and personal factors.

Background and Aims: As the hearing aid technology progressively promotes toward replacing analog hearing aids with digital and programmable ones, comparison of the patient satisfaction of those kinds of hearing aids by means of a valuable tool seems so necessary. So, the aim of this study was to compare self-reported benefit of analog, digitally controlled programmable and digital hearing aids for reducing disability caused by hearing impairment in mild to severe sensorineural hearing impaired persons.
Materials and Methods: This cross-sectional study was performed on 90 persons with mild to severe sensorineural hearing loss dividing into three groups: 43 subjects were fitted with digital, 15 with programmable, 23 with analog hearing aids. After pure tone audiometry, Abbreviated profile of hearing aid benefit (APHAB) was completed before and one month after using hearing aids to determine the benefit of them.
Results: Global APHAB mean scores for digital, programmable and analog hearing aids were 49.05, 33.19 and 39.53, respectively. Ease of Communication subscale mean scores were 53.46 for digitals, 37.66 for programmables and 39.09 for analogs. Background noise subscale mean scores for digital programmable and analog hearing aids were 46.36, 25.53 and 35.31, respectively. Global and also both subscale mean scores showed significant difference between digital hearing aids and programmable and analog ones. There was no significant difference between reverberation subscale mean scores of three groups.
Conclusion: It seems digital hearing aids may be more beneficial to reduce disability caused by hearing loss than analog and programmable hearing aids are.