Frye FONIX FP40D - Manual (Page 84)

76 FONIX FP40 Portable Hearing Aid Analyzer
5.1.1.3 To set up an external sound field speaker
If you have a permanent location for your analyzer, you may find it more convenient to use an
external sound field speaker for your real-ear measurements. This external sound field speaker can
be mounted on either a floor stand or a swing arm. See Figure 5.1.1.3 for an example of the swing
arm setup.
When performing real-ear measurements, plug in this sound field speaker to the jack on the back of
the FP40 labeled “External Speaker.”
Figure 5.1.1.3—External speaker setup
5.1.2 Setting up the client for testing
To set up the client for testing, you need to position the client in relation to the sound field speaker,
place the earhook and the reference microphone appropriately, insert the probe tube, and level the
sound field speaker.
5.1.2.1 To position the sound field speaker
The sound field speaker should be about 12 inches (30 cm) from the surface of the client’s head
(near the temple) and pointing toward the ear to be tested. We recommend an azimuth angle of 45
degrees (halfway between the client’s nose and ear). The height of the loudspeaker should be level
with, or a little above the ear. See Figure 5.1.2.