Interacoustics Affinity2.0 Quick Manuals page 67

Own Mould versus SPL Probe
Whether the RECD is performed using the client's own ear mould or the SPL probe may have an effect on the
result. The benefit of using the client's own ear mould is that the measurement will reflect your client's actual
residual volume whereas the SPL probe only provides an estimate. However, you may be in a situation where
the ear mould is nonexistent, broken, or has an extremely bad fit. Furthermore, you might need to conduct
measurements on children not willing to co-operate. In these situations the SPL probe offers the benefit of easy
probe placement and measurement.
Below, see two RECD measured in the same ear using the SPL probe and own ear mould respectively. Note:
the differences between the two ways of measuring. As can be seen above the curve measured with the client's
own ear mould is below 0 in the low frequencies. This may be due to ear mould effects such as the tightness of
the fit and venting and in the insertion depth of the SPL probe or ear mould.
RECD WITH SPL PROBE RECD WITH OWN EAR MOULD
Using the RECD in the hearing aid fitting
The RECD can now be used for the hearing aid fitting. The RECD can be imported, if that feature is supported,
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manually into the hearing aid software. The fitting will be recalculated while taking the RECD into account . To
view the RECD values, click on Table View
To proceed with the hearing aid verification, click on the REAR button; the software will automatically go into the
coupler mode and it will then be possible to proceed with the verification. The default fitting formula will be
DSL v5 Pediatrics. Use the hearing aid software to fine tune the hearing aid and to ensure that the output is
matching the DSL targets for soft, average, and loud, using a speech stimuli (like the ISTS). Measure the MPO
to ensure that the output for loud sounds is not hitting the UCL.
Visible Speech Mapping can also be used for coupler based fittings. This can be done by choosing the Visible
Speech Mapping in the REM module, rather than the REM440 module it self. Note that Visible Speech Mapping
requires a separate license.
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For more information, please consult the Affinity Additional Info and Callisto™ Additional Info documents,
available on our website www.interacoustics.com
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Not all hearing aid manufacturers' software support the import of RECDs. If unsure, check with the hearing aid
manufacturer.
Item No. 8105091 – 12/2013
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