Orban Optimod-AM 9400 Operating Manual Download

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OPERATION ORBAN

MODEL

9400

audible distortion with almost any program material. Large changes in the fre-
quency balance of the compressor outputs will change this tuning, leaving the 9400
more vulnerable to unexpected audible distortion with certain program material.
Therefore, you should make large changes in EQ with the bass and parametric
equalizers and the HF enhancer, because these are located

before

the compressors.

The compressors will therefore protect the system from unusual overloads caused by
the chosen equalization. Use the multiband mix controls only for fine-tuning.

You can also get a similar effect by adjusting the compression threshold of the indi-
vidual bands. This is comparably risky with reference to clipper overload, but unlike
the

AND

controls, does not affect the frequency response when a given band

is below threshold and is thus producing no gain reduction.

Advanced Multiband Controls

The following Advanced Multiband controls are available only from 9400 PC Remote
software.

Bx On / Off

switches allow you to listen to any band (or any combination of bands)

independently. This is a feature designed for intermediate or advanced users and
developers when they are creating new 9400 presets.

Please note that a single band will interact with the back-end clipping system quite
differently than will that band when combined with all of the other bands. There-
fore, do not assume that you can tune each band independently and have it sound
the same when the clipping system is processing all bands simultaneously.

B1-B5 Attack (Time)

controls set the speed with which the gain reduction in each

band responds to level changes at the input to a given band’s compressor. These
controls, which have never previously been available in an Orban processor, are risky
and difficult to adjust appropriately. They affect the sound of the processor in many
subtle ways. The main trade-off is “punch” (achieved with slower attack times) ver-
sus distortion and/or pumping produced in the clipping system (because slower at-
tack times increase overshoots that must be eliminated in the clipping system). The
results are strongly program-dependent, and must be verified with listening tests to
a wide variety of program material.

The

TTACK

time controls are calibrated in arbitrary units. Higher numbers corre-

spond to slower attacks.

In the analog AM channel, the look-ahead delay times in bands 3, 4, and 5 auto-
matically track the setting of the

TTACK

time controls to minimize overshoot for any

attack time setting.

High Frequency Limiter

(AM chain only) sets the amount of additional gain reduc-

tion occurring in band 5 when high frequency energy would otherwise cause exces-
sive distortion in the final clipper. It uses an analysis of the activity in the final clipper
to make this determination, and works in close cooperation with the band-5 multi-
band clipper. Functionally, this control is a mix control that adds a HF limiter gain re-
duction signal to the band 4 gain reduction signal to determine the total gain re-