Orban Optimod-PC 1101 Operating Manual Download

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OPERATION

ORBAN MODEL 1101

setting of the

ASS

boost control (in the Equalization screen). Thus, without in-

troducing obvious coloration, the gating smoothly preserves the average overall
frequency response “tilt” of the five-band compressor, broadly maintaining the “au-
tomatic equalization” curve it generates for a given piece of program material.

If the

GATE

control is turned

, the

ASS

control (in the Equaliza-

tion screen) is disabled.

MB Downward Expander

(“Multiband Downward Expander Threshold”) deter-

mines the level below which the single-ended noise reduction system’s downward
expander begins to decrease system gain and below which the high frequencies be-
gin to become low-pass filtered to reduce perceived noise. There are two controls:
the

OWN

XPANDER

control sets the expansion threshold in Bands 1-4, while the

OWN

XPANDER

control sets the expansion threshold in Band 5. Activate the sin-

gle-ended dynamic noise reduction by setting these controls to a setting other than

The single-ended noise reduction system combines a broadband downward ex-
pander with a program-dependent low-pass filter. These functions are achieved by
causing extra gain reduction in the multiband compressor. You can see the effect of
this extra gain reduction on the gain reduction meters.

Ordinarily, the gating on the AGC and multiband limiter will prevent objectionable
build-up of noise and you will want to use the single-ended noise reduction only on
unusually noisy program material. Modern commercial recordings will almost never
need it. We expect that its main use will be in talk-oriented programming, including
sports.

Please note that it is impossible to design such a system to handle all program mate-
rial without audible side effects. You will get best results if you set the

OWN

XPANDER

control of the noise reduction system to complement the program mate-

rial you are processing. The

OWN

XPANDER

should be set higher when the input

is noisy and lower when the input is relatively quiet. The best way to adjust the

OWN

XPANDER

control is to start with the control set very high. Reduce the control

setting while watching the gain reduction meters. Eventually, you will see the gain
increase in sync with the program. Go further until you begin to hear noise modula-
tion—a puffing or breathing sound (the input noise) in sync with the input program
material. Set the

OWN

XPANDER

control higher until you can no longer hear the

noise modulation. This is the best setting.

Obviously, the correct setting will be different for a sporting event than for classical
music. It may be wise to define several presets with different settings of the

OWN

XPANDER

control and to recall the preset that complements the program ma-

terial of the moment.

Note also that it is virtually impossible to achieve undetectable dynamic noise reduc-
tion of program material that is extremely noisy to begin with, because the program
never masks the noise. It is probably wiser to defeat the dynamic noise reduction
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.