FONIX® 8000 - Frye Electronics

134 FONIX 8000 Hearing Aid Test System
16. Amplitude: This is the test level used to measure the curve.
17. Frequency: This is the frequency used to measure the curve. When the source
type is set to Composite, this is shown as COMP. When the source type is set to
COMP DSP, this is shown as CMPD.
18. Leveling status. This is the status of leveling when the measurement was taken.
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Figure 6.4—Directional Polar display
6.4.2 Testing in Simultaneous Mode
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By default, when you enter the Directional Polar screen, you will be in
“Simultaneous Mode.” Simultaneous mode was designed as a fast test that tells
you the polar plot response of the hearing aid at eleven important frequencies
using only one rotation of the hearing aid.
Simultaneous mode uses the broadband Composite signal (with the ANSI filter) at
60 dB SPL by default, although the user can adjust these characteristics by using
the arrow keys to change the input level and the local menu to change the signal
settings. (It is important to test the hearing aid below its compression kneepoint
and above its expansion kneepoint to ensure any reductions in amplification are
from its directional characteristics instead of its AGC functionality.) If the tested
hearing aid is open fit, you may need to switch to the COMP DSP signal. The
COMP DSP signal uses a different type of signal averaging that works better for
hearing aids with advanced processing. Use the [F5] key to change the signal type
to COMP DSP if desired.