Developing an Appropriate Digital Hearing Aid for Low-Resource Countries: A Case Study

Table 7

Electroacoustics of the commercial-ready version.

Electroacoustics (IEC 60118-7)	Commercial-ready version
Max OSPL90 118 dB (±4 dB)	125 dB
OSPL90 @ 1 KHz 114 dB (±4 dB)	118 dB
Max FOG 45–55 dB (+5 dB)	71 dB
FOG @ 1 KHz 42 dB (+5 dB)	62 dB @ 50 dB
Basic frequency response 200–4500 Hz	380–4400 Hz
THD @ 70 dB SPL input 500 Hz < 5%, 800 Hz < 5%, 160 Hz < 2%	0.3%, 3.8%, 0.4%
Equivalent input noise level <25 dB SPL	25 dB
Battery current < 1 mA	11.8 mA (rechargeable)