Orban OPTIMOD-FM 8700, Operating Manual

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3-70
OPERATION ORBAN MODEL 8700i
velopers when they are creating new 8700i presets. The mute control for a given
band affects
both the FM and HD processing because it mutes the input of compres-
sor in that band. This prevents the muted compressor’s sidechain from producing a
gain reduction signal that could couple into unmuted bands through the various
band-coupling controls.
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.
Advanced Multiband and Band Mix Controls
The following Multiband and Band Mix controls are found only in the Advanced
Modify screen.
Compression Threshold; Speech Compression Threshold controls set the compression
threshold for music and speech in each band (following the 8700i’s automatic
speech/music discriminator), in units of dB below the final clipper threshold. We rec-
ommend making small changes around the factory settings to avoid changing the
range over which the
MB C
LIPPING
control operates. These controls will affect the
spectral balance of the processing above threshold, but are also risky because they
can significantly affect the amount of distortion produced by the back-end clipping
system.
You can use these controls to set independent frequency balances for music and
speech (page 3-73).
B1-B5 Attack (Time); Speech B1-B5 Attack 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 for music and speech respectively, following the 8700i’s automatic
speech/music detector. These controls 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) versus distortion and/or pumping pro-
duced in the clipping system (because slower attack 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.
Because there are separate controls for music and speech (page 3-73), you can set
attack times faster for speech (to minimize clipping distortion) and slower for music
(to maximize punch and transient definition).
The
A
TTACK
time controls are calibrated in arbitrary units that very approximately
correspond to milliseconds. Higher numbers correspond to slower attacks.
The look-ahead delay times in bands 3, 4, and 5 automatically track the
setting of the
A
TTACK
time controls to minimize overshoot for any attack
time setting.