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Testing FM Systems with FONIX 6500-CX Analyzers
1.6.6 Test environmental mic response with typical input — EEF65
1. Set up the environmental microphone for testing as described in Section 1.4.3. Set
the FM receiver to receive FM+ENV signals. If the sound field speaker is leveled,
you don’t have to re-level it.
2. Press
[
∨
] to select CRV 3.
3. Press [<, >] to set the source level to 65 dB SPL.
4. Press [START/STOP] to start the measurement.
5. When the measurement has stabilized, press [START/STOP] again to stop the meas-
urement. This measurement will be referred to as EEF65.
6. Compare all three curves. CRV 1 should be EHA65, CRV 2 should be EFE80, and
CRV 3 should be EEF65. For a successful fit, EHA65 and EEF65 should be similar,
and EFE80 should be 7-10 dB higher. See Figure 1.6.6.
Figure 1.6.6
Comparison of EHA65 (CRV1), EFM 80 (CRV2), and EEF65 (CRV),
the environmental microphone response at 65 dB SPL
