Harsh Sibilance ("Ess" Sounds) In The Hd Channel; Hd And Fm Levels Do Not Match When The Receiver Crossfades; Digital Radio Loudness Cannot Be Set Using The Digital Output 100% Peak Level Control; Loudness Drops Momentarily During Hd Radio Analog/Digital Crossfades - Orban OPTIMOD-FM 8500S Operating Manual

OPTIMOD-FM DIGITAL

Harsh Sibilance ("Ess" Sounds) in the HD Channel

Adjust the HD D
E
See page 3-72.

HD and FM Levels Do Not Match When the Receiver Crossfades

Adjust the HD L
IMIT
Do not match levels by adjusting the output level of the output driving the HD ex-
citer. Only use this control to match the peak levels of the Optimod output to the
exciter. In other words, if the exciter is set to clip when it receives at –3 dBfs, adjust
the Optimod output level to –3 dBfs. This uses all of the headroom available in the
transmission channel, minimizing the amount of look-ahead limiting that the Opti-
mod needs to do.
If you have accidentally turned on the BS.1770 Safety Limiter, this will cause the
loudness to be lower than expected in HD Radio applications. Turn it off. See step 12
on page 2-35.
Digital Radio Loudness Cannot be Set Using the Digital Output 100% Peak Level Con-
trol
When the BS.1770 Safety Limiter is ON, adjusting the HD-assigned 100% P
sets only the output headroom, not loudness. See step 12 on page 2-35.
C
ONTROL

Loudness Drops Momentarily During HD Radio Analog/Digital Crossfades

The analog and digital channels in your transmission path have reversed polarity
with respect to each other and a phase cancellation is occurring in the radio during
crossfades. You can correct this with the HD P
page 3-68.

HD Frequency Response is Limited to 15 kHz

The HD B
ANDWIDTH
Even if the HD B
ANDWIDTH
kHz if the HD output's sample rate is set to 32 kHz and/or if the sample rate of the
audio applied to the 8500S's digital input is 32 kHz. 20 kHz response requires sample
rates to be set to 44.1 kHz or higher.

You Cannot Set Any Output to Emit an HD Signal

From the main menu, Locate to S
8500S/FM. The 8500S/FM is the same as the 8500S/HD except that the 8500S/FM does
not provide digital radio processing. The 8500S/FM can be upgraded to an 8500S/HD
in the field by installing the plug-in control module contained in the 8500SUPG/HD
upgrade kit, which can be purchased from your Orban dealer.

General Dissatisfaction with Subjective Sound Quality

The 8500S is a complex processor that can be adjusted for many different tastes. For
most users, the factory presets, as augmented by the gamut offered by the L
control for each preset, are sufficient to find a satisfactory "sound." However,
M
ORE
some users will not be satisfied until they have accessed other Modify Processing
control and/or activate the HD channel's band 5 compressor.
-E
SS
D control in the on-air preset to match levels. See page 3-71.
R
control might be set to 15 kHz. See page 3-68.
control is set to 20 kHz, bandwidth will be limited to 15
YSTEM
or FM P
OLARITY
S > D to see if your unit is an
ETUP IAGNOSTICS
TROUBLESHOOTING
L
EAK EVEL
controls. See
OLARITY
-
ESS
5-7