DSL FP40 method - Frye Electronics

Note: When testing ITE/ITCs use an HA-1 coupler. Attach the insert earphone to
the coupler using a standard foam-tip and putty.
The resulting curve is labeled AIDED RESPONSE on the small graph on the
right side of the LCD display.
DSL Method Using FP40/FP40-D
Custom earmold
IV. RECD INFORMATION
To 3A
insert earphone
Probe mic
Figure 2
You will see two curves in the right side graph of the screen display. One curve will be
the result of the coupler-based measurement, the second will be the result of the real ear
measurement. The difference between these two curves is the real-ear-to-coupler difference
(RECD) values across frequencies. This is displayed as the INSERTION curve on the
large graph on the display. To get the data for this curve, press the DATA button. The
RECD data will be displayed for individual frequencies from 200–8000 Hz. The FP40
labels this PROBE INSERTION. Since the curves have been saved as the unaided and
aided responses, the software assumes that the Real Ear Insertion Response (REIR) has
been measured. In fact, the RECD has been measured. Print and save these test results.
Version 3.30 and higher: To calculate the RECD values subtract the AIDED 1 data from
AIDED 2 at the required DSL frequencies.
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