Orban OPTIMOD-FM 8700, Operating Manual

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3-2
OPERATION ORBAN MODEL 8700i
Screen Display supplies control setting information and screen help, and displays the
gain reduction and level meters (described directly below).
The 8700i’s color LCD displays the following meters and indicators:
In meters show the peak input level applied to the 8700i’s analog or digital inputs
with reference to 0 dB = digital full-scale. If the meter reads at the top of the scale
and the analog input is active, this indicates clipping in the A/D converter.
AGC meters show the gain reduction of the slow AGC processing that precedes the
multiband compressor. Full-scale is 25 dB gain reduction.
The AGC is a two-band unit with Orban’s patented bass coupling system.
The two meters indicate the gain reduction of the AGC Master and Bass
bands.
Gate indicators show gate activity. They light when the input audio falls below the
threshold set by the gate threshold controls. (There are two gating circuits—one for
the AGC and one for the multiband limiter—each with its own gate threshold con-
trol.) When gating occurs, the AGC and compressor’s recovery times slow drastically
to prevent noise rush-up during low-level passages.
Multiband gain reduction meters show the gain reduction in the multiband compres-
sor. Full-scale is 25 dB gain reduction. The
MB GR M
ETER
switch (in
I
NPUT
/O
UTPUT
>
U
TILITIES
) determines what signals the 2-Band and 5-Band Compressor gain reduc-
tion meters indicate. The switch can be set to
FM
,
HD
(digital radio), or
S
PLIT
. In
S
PLIT
mode, the 8700i’s front panel display shows the gain reduction of the FM ana-
log multiband compressors on the left side of the split meters and the gain reduc-
tion of the digital radio compressors on the right. If the left and right channel gain
reductions are not identical in a given band of the 2.0 processing, that band’s meter
displays the larger of the left or right channel gain reductions.
Many editing modes display small gain reduction meters in a window on the left
side of the 8700i’s front-panel screen. In
S
PLIT
mode, these meters are context-
sensitive. They show the FM channel gain reduction when you are in an FM pro-
cessing screen and show the HD gain reduction if you are in an HD processing
screen. If the screen is not clearly FM or HD, the meters show the HD gain reduction.
A “GR” label below the meters indicates whether the meters are displaying FM or
HD gain reduction. A field below the meters indicates whether the meters are show-
ing FM or HD gain reduction and whether the 8700i’s speech/music detector is de-
tecting speech or music.
8700i PC Remote displays the gain reduction of the analog FM and HD multiband
compressors on two metering groups, each containing either two and five meters.
All meters are split and show the left and right channel gain reductions. A horizon-
tal scroll bar below the meters allows you to drag the display left or right to expose
the meters you wish to see.
If the Five-Band structure is active, all the meters on the main meter
screen display gain reduction (G/R) activity. If the Two-Band structure is
active, only the two leftmost meters display G/R activity.