Orban OPTIMOD-FM 8700, Operating Manual

Page: 296 / 390

5-6
TROUBLESHOOTING ORBAN MODEL 8700i
System Will Not Pass Emergency Alert System (“EAS” USA Standard) Tones at the Le-
gally Required Modulation Level
See System Will Not Pass Line-Up Tones at 100% Modulation (directly above) for an
explanation. These tones should be injected into the transmitter after the 8700i, or
the 8700i should be temporarily switched to
BYPASS
to pass the tones.
System Receiving 8700i’s Digital Output Will Not Lock
Be sure that the 8700i’s output sample rate is set to match the sample rate that the
driven system expects. Be sure that the 8700i’s output mode (AES3 or SPDIF) is set to
match the standard expected by the driven system.
19 kHz Frequency Out-of-Tolerance
First, verify that a problem really exists by using a second frequency-measuring de-
vice and/or verifying the problem with a monitoring service. If the problem is real,
contact Orban Customer Service; there is no frequency trim available. The crystal is a
surface-mount part and is not easily field-replaceable.
L–R (Stereo Difference Channel) Will Not Null With Monophonic Input
This problem is often caused by relative phase shifts between the left and right
channels prior to the 8700i’s input. This will cause innocuous linear crosstalk be-
tween the stereo main and subchannels. Such crosstalk does not cause subjective
quality problems unless it is very severe.
Talent Complains About Delay in Their Headphones
Dedicate an output to low-delay Monitor mode and use this to drive headphones.
See
Monitoring on Loudspeakers and Headphones on page 1-26, and step 17 on
page 2-38. Alternatively, use an Ultra-Low-Latency (UL) preset. See Ultra-Low-
Latency Five-Band on page 3-22.
HD Output Sounds Too Bright
Enable adjustment of the HD output’s spectral balance by putting the on-air preset
into
I
NDEPENDENT
mode. Do this by setting the FM

HD C
ONTROL
C
OUPLING
control in
the HD L
IMITING
page of A
DVANCED
C
ONTROL
to I
NDEPENDENT
. You can also toggle this
control via two buttons on the button bar in 8700i PC Remote. See page 3-74.
In this mode, the HD processing channel’s equalizer, five-band compressor, and
band-mix controls are independent of the corresponding controls in the FM channel
and can be adjusted separately. You can therefore fine-tune high frequencies by ad-
justing the equalizer, parameters in the band 4 and band 5 compressors, the band 4
and band 5
B
AND
M
IX
controls, and the HD D
E
-
ESS
control. One of the most effective
ways to tame harsh high frequencies dynamically is to activate the HD channel’s
band 5 compressor. See
HD Audio Controls on page 3-81.
Harsh Sibilance (“Ess” Sounds) in the HD Channel
Adjust the
HD D
E
-E
SS
control and/or activate the HD channel’s band 5 compressor.
See page 3-83.
HD and FM Levels Do Not Match When the Receiver Crossfades
Adjust the HD L
IMIT
D
R
control in the on-air preset to match levels. See page 3-82.