76 The DSL/NAL-NL1 Module WinCHAP User’s Manual
6.3.7 Measuring with Pure-tones
The FONIX FP35, 7000, and FP40 analyzers are equipped with several differ-
ent types of pure-tone measurements. The “Normal” pure-tone sweep performs
a standard sweep once and automatically stops. The “Fast” sweep measures 16
different frequencies repeatedly until the user stops the test. The “Short” sweep
measures 10 different frequencies once and automatically stops.
WinCHAP automatically specifies the Short signal when performing real-ear
measurements at 90 dB SPL. This means that only one quick sweep will be run
before the test automatically terminates.
You can choose whether you want to use a Normal or a Fast sweep when per
-
forming pure-tone measurements below 90 dB SPL by changing the PT Signal
Mode in the Settings window.
Notes:
• The 6500-CX does not have the Fast or Short selections available. Real-ear
pure-tone measurements are performed using only frequencies specified by
NAL and DSL. Coupler measurements are performed with a Normal pure-tone
sweep.
• The FP40 is not very responsive to computer commands during a Fast sweep
when the reference microphone is on. During those conditions, WinCHAP
will only perform only one sweep before terminating the test.
6.4 NAL-NL1 Verification
The NAL-NL1 window is used to fit a hearing aid to the NAL-NL1 fitting for-
mula. You can choose to perform the fitting with insertion gain or gain targets;
any measurement taken in one scaling is automatically converted for use with
the other scaling. The SSPL90 selection is used for testing output at loud levels.
See Figure 6.4.
