Advanced Multiband Controls - Orban Optimod-FM 8300 Operating Manual

OPTIMOD-FM DIGITAL
helps prevent distortion in the final clipper when the input program material con-
tains excessive energy above 6 kHz.
The Band 5 multiband clipper operates at 256 kHz and is fully anti-aliased.

Advanced Multiband Controls

The following Advanced Multiband controls are available only from 8300 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 8300 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.
Lookahead activates or defeats the look-ahead functionality in the multiband
compressor / limiter. Defeating look-ahead improves transient impact at the expense
of distortion, particularly on speech. To mitigate this tradeoff, a selectable "auto"
mode turns look-ahead on for speech material and off for music, using an automatic
speech/music detector. Switching is seamless and click-free because we change the
delay in the compressor control sidechains; this is not a way to reduce the 8300's
throughput delay.
Choices are L
OOKAHEAD
Speech is detected if (1) the input is mono, and (2) there are syllabic
pauses at least once every 1.5 seconds. Speech with a stereo music back-
ground will usually be detected as "music," or the detector may switch
back and forth randomly if the stereo content is right at the stereo /
mono detector's threshold. Mono music with a "speech-like" envelope
may be incorrectly detected as "speech." Music incorrectly detected as
"speech" will exhibit a slight loss of loudness and punch, but misdetec-
tion will never cause objectionable distortion on music.
Speech that is not located in the center of the stereo sound field will al-
ways be detected as "music" because the detector always identifies ste-
reo material as "music." This can increase clipping distortion on such
speech.
If the B
matically set it to M
(unless L
and bass clipping will stay H
Speech always sounds cleaner with M
creased bass "punch" supplied by H
This control does not affect the HD processing chain.
B1-B4 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
, and A .
I , O
N UT UTO
C M is set to H
ASS LIP ODE
when speech is detected and H
EDIUM
is L , in which case M
ATENCY OW
ARD
, the speech/music detector will auto-
ARD
bass clipping is unavailable
EDIUM
).
bass clipping and the in-
EDIUM
is irrelevant to speech.
ARD
OPERATION
otherwise
ARD
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