61
FM
FM Final Limiter (Clipper) (Basic Tab)
The
Ultra LoIMD main clipper
is the Omnia.11’s
final limiting stage for the analog FM channel.
Here is where the
Omnia.11’s loudness
and
quality
advantage is most evident! This new extremely
powerful new algorithm utilizes a great amount of
DSP power and is designed to reduce clipper
-
induced IM distortion to the bare minimum across
the entire audio bandwidth, providing new,
previously unheard of levels of clarity and
loudness with minimal side
-
effects.
Touch the
FM
icon
button to access the
5 variable
controls located here: Clipper
Drive
,
Auto Sense
,
Comp Clip Drive
,
Voice Quality
and
BS-412
Drive
.
Clipper Menu (Basic Tab)
The
clipper
Drive
c
ontrol
(which also appears in the
Quick
Setup tab as
Clipper
Drive) adjusts
the depth of
clipping
of the pre-emphasized audio
in precise 0.1dB steps over a +/
-
6 dB range. This is the primary control over
the “loudness vs. disto
rtion” tradeoff. It is advisable to make minor changes, primarily as the 'loudness fine tuner'.
Be careful! There is a lot of available power here!
Note: If this control is grayed
-out, go to the
FM Options
submenu of the Output menu and ensure that the
BS-412
control is turned off.
We suggest that each time you try a new factory preset, you adjust the Clip Drive as follows:
Start by turning the
Auto
Sense
control all the way down to 0.0. Then adjust the c
lipper
Drive
control down in 0.5dB steps until the
loudness
just
falls off too much, then bring it up a bit from there. That is the correct setting
for you
for the currently
selected preset. On some presets, you may need to turn it up instead of down. This is OK too. Adjust it up in the
same 0.5db steps until you achieve the loudness required or the sound becomes too distorted, whichever comes first.
If the distortion comes first, you probably need to start with a more aggressive preset.
Finally, turn up the
Auto Sense
until about
0.5 to 1.0 dB of activity can be seen on the Auto Sense meter.
NOTE:
If you are turning up the Clip Drive to increase loudness and you reach a point where the loudness and
distortion do not seem to be
increasing as you would expect, you have likely run into the
Auto Sense
ceiling. Try
turning down the
Auto Sense
control a little. (See below) This will allow more clipping to take place.
More about
Auto Sense:
This special algorithm senses the “duty cycle” of the clipper by watching for excessive
clipper activity that may cause distortion. A setting of “0.0” turns Auto Sense off. Higher settings will automatically
detect excessive clipping and reduce the clipper drive when needed.
Hint:
It
can be helpful, especially when tuning the processing for maximum loudness, to
initially set
Auto Sense
down to
“0.0”,
adjust the clipper
Drive
to the lowest possible setting that provides the loudness needed,
then finally
turn the
Auto Sense
control up until
the Auto Sense meter
just starts to deflect
(about 1dB on peaks)
.
NOTE:
Try
experimenting with the balance between Clipper Drive and Auto Sense for your best loudness vs. distortion
compromise. Try not to let the Auto Sense average gain
-
reduction exceed about 2dB though. Shor
t-
term peaks
above that are fine.
