Orban OPTIMOD-FM 8600, Operating Manual

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OPTIMOD-FM DIGITAL OPERATION
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with this sort of material (traffic reports from helicopters and the like) to avoid ob-
jectionable side effects. You must let your ears guide you.
Band 5 is particularly critical for noise reduction because much of the Downward Ex-
pander’s utility lies in hiss reduction. Hiss has most of its energy in band 5, while
program material typically has less energy in this band, so the
B5 D
OWN
E
XPANDER
D
ELTA
T
HRESHOLD
control’s setting is critical to removing hiss while minimizing re-
moval of desired program energy.
Starting in V2.0, the Downward Expander’s dynamic frequency response is no longer
constrained to being strictly lowpass—Band 5 is now uncoupled from the lower
bands, so the band 5 downward expander can produce less gain reduction than oth-
er bands. This can help prevent loss of desired high frequency material in the pro-
gram.
Band 3 > 4 Coupling control determines the extent to which the gain of band 4
and 5 (centered at 3.7 kHz) is determined by and follows the gain of band 3 (cen-
tered at 1 kHz). Set towards 100% (fully coupled) it reduces the amount of dynamic
upper midrange boost, preventing unnatural upper midrange boost in light pop and
instrumental formats.
Band 4 > 5 Coupling control determines the extent to which the gain of band 5
(6.2 kHz and above) is determined by and follows the gain of band 4.
The sum of the high frequency limiter control signal and the output of
the
B
AND
4 > 5 C
PL
control determines the gain reduction in band 5. The
B
AND
4 > 5 C
PL
control receives the independent left and right band 4
gain control signals; this feed is unaffected by the band 4
M
AX
D
ELTA
G/R
control. Range is 0 to 100% coupling.
Band 3 > 2 Coupling and Band 2 > 3 Coupling controls determine the extent to
which the gains of bands 2 and 3 track each other.
When combined with the other coupling controls, these controls can ad-
just the multiband processing to be anything from fully independent op-
eration to quasi-wideband processing.
Band 2 > 1 Coupling control determines the extent to which the gain of band 1
(below 100 Hz) is determined by and follows the gain of band 2 (centered at 400
Hz). Set towards 100% (fully coupled) it reduces the amount of dynamic bass boost,
preventing unnatural bass boost in light pop and talk formats. Set towards 0% (in-
dependent), it permits frequencies below 100 Hz (the “slam” region) to have maxi-
mum impact in modern rock, urban, dance, rap, and other music where bass punch
is crucial. The default setting is 30%.
MB Band Mix controls determine the relative balance of the bands in the multi-
band compressor. Because these controls mix after the band compressors, they do
not affect the compressors’ gain reductions and can be used as a graphic equalizer
to fine-tune the spectral balance of the program material over a
±
6 dB range.
There are two sets of mixer controls, one for the analog processing chain and one
for the HD processing chain. The mixer controls for the HD processing chain also de-
termine the spectral balance of the low-delay monitor output.