HP RM500SL - Manual (Page 38)

0611 RM500SL User’s Guide Version 2.8 Page 38
8 ANSI S3.22 Hearing Aid Tests
8.1 Section overview
FastFacts 8.1: ANSI S3.22 hearing aid tests
8.2 ANSI S3.22-1996 facts
FastFacts 8.2: ANSI S3.22-1996 facts
The RM500SL performs selected hearing instrument tests in accordance with
ANSI S3.22-1996. This standard expresses some outputs and gains as High
Frequency Average (HFA) values. The HFA is the average of values at 1000,
1600 and 2500 Hz. If a hearing aid meets certain conditions, the manufacturer
may choose other averaging frequencies called Special Purpose Average (SPA)
frequencies. The current averaging frequencies are indicated explicitly on test
results where space permits and also appear as tick marks on the frequency axis
of graphs. To change the averaging frequencies, see
7.7: ANSI test frequencies .
This standard also requires some tests with the gain control full on and some with
the gain control in the Reference Test Position (RTP). This requirement applies to
both Linear and AGC aids that have a HFA (or SPA) full-on gain greater than the
HFA (or SPA) OSPL90 minus 77 dB. Otherwise the RTP is full on. If required, the
RM500SL will pause in its testing and guide you in setting the gain control to the
RTP.
All other controls on the hearing instrument should be set to provide the widest
frequency response, the greatest gain and the highest maximum output. AGC
controls or programmable settings should be as designated by the manufacturer.
At full-on gain the [Linear] and [AGC] test sequences provide a curve of OSPL90
(Output Sound Pressure Level for a 90 dB input SPL), the HFA (or SPA) and peak
value of this curve, the frequency of the peak and the HFA (or SPA) gain for a 50
dB input SPL.
With the gain control at RTP, these sequences also provide a frequency response
curve with an input SPL of 60 dB (Linear) or 50 dB (AGC), the HFA (or SPA) gain
for a 60 dB input SPL, the frequency range, battery drain, equivalent input noise,
harmonic distortion, attack and release time (AGC only).
These Hearing Instrument Tests follow the procedures of ANSI S3.22-1996 or
ANSI S3.22-2003 as selected in Setup. See
7.6: 1996 or 2003 ANSI standard :
Linear: An automated test sequence for linear hearing aids per ANSI S3.22.
AGC: An automated test sequence for AGC hearing aids per ANSI S3.22.
Input/Output: 1 - 4 curves of coupler SPL vs input SPL at .25, .5, 1, 2 and 4 kHz.
Telecoil: STS (1996 - simulated telephone sensitivity) or RSETS (2003 - relative
simulated equivalent telephone sensitivity) using a coil in the test chamber floor.
This section covers the following topics:
8.2: ANSI S3.22-1996 facts 8.7: ANSI input-output curves
8.3: ANSI S3.22-2003 facts 8.8: ANSI telecoil terminology
8.4: ANSI 1996 Linear and AGC tests 8.9: ANSI telephone simulator (TMFS) test
8.5: ANSI 2003 Linear and AGC tests 8.10: Telecoil test results
8.6: ANSI test results