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Comparison of linear and K-Amp circuits
R K Surr1, M T Cord, B E Walden
1Walter Reed Army Medical Center, Washington, D.C., USA.
Objective:
To evaluate hearing aid user preference for Linear Class D or Class D with K-Amp circuit.
Design:
Eighteen subjects, experienced with Class A hearing aid use, were given a choice of binaural hearing aids with either Linear Class D circuits or Class D with K-Amp circuits after consecutive 30 day trial periods with each set of instruments. The patients also rated the benefit obtained from each circuit using the Profile of Hearing Aid Benefit (PHAB).
Results:
There was no significant difference in the number of subjects who chose one or the other of the circuits. Further, the PHAB scores showed no statistically significant differences between the two circuits. In most cases, the instruments rated highest on each of the subscales by an individual subject were also the ones preferred based on the 30 day trial.
Conclusions:
Hearing aids with either Class D Linear or Class D with K-Amp circuits provided significant benefit in many everyday listening environments for individuals with a mild to moderate degree of hearing loss. Subjective choice between the Linear Class D and the K-Amp circuits was relatively evenly divided.
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