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FM-531HD / May 2013
F M - 5 3 1 H D P R O G U I
31 Band FM Limiter Sidebar
Just like the five band AGC/Compressor, there is a sidebar
with some special adjustments available to the user to tailor
the sound of the 31‑band limiter. It should be noted first that
all bands of audio processing can be adjusted as a group or
independently in the sidebar menus. For more information
on how to adjust these controls, please see the “FM‑531HD
Graphical Interface Operation” section of this chapter.
Threshold
The Threshold control determines at what level limiting
will start in a particular band. The range for the FM‑531HD
limiter threshold controls is adjustable over a 12dB range and they work in concert with
the 31‑band Limiter Drive to set the individual band’s operating behavior.
Attack
The Attack control determines how quickly the limiter will respond to audio once it
exceeds the limiter threshold. Recommended attack time settings are between 30 and
10ms. Longer attack times are possible for frequencies below the VBMS frequency
setting. Overall, longer attack times will cause the look ahead limiter to work harder
and/or overshoot.
Release
The Release control determines how quickly the limiter will return to 0dB once audio
has fallen below the limiter threshold. Faster release times will yield a louder sound
while slower times will yield a smoother sound at the expense of loudness.
Because of the way the 31‑band limiter works, there is a lot of leeway with attack
and release times and these controls have been set so that the end user doesn’t drive the
car “off the cliff.” Basically, only extreme settings will yield a totally undesired sound.
That being said, these controls should also not be adjusted haphazardly.
Main Clip Drive
The Main Clip Drive controls the absolute peak output level of the
31‑band section and is adju/‑6dB. The resolution of this control
is 0.05dB, fine enough for the most exacting output level adjustments.
Pre-Emphasis
FM Pre-Emphasis is selectable as 50 or 75 microseconds, or Flat
(OFF).
Summary of Contents for FM-531 HD
Page 2: ...Technical Manual Wheatstone Corporation May 2013 FM HD Digital Audio Processor FM 531hd...
Page 122: ...page A 2 FM 531HD May 2013 A P P E N D I C E S Appendix A General Specifications A 3 Contents...
Page 128: ...page A 8 FM 531HD May 2013 A P P E N D I C E S Appendix B FM 531HD GPI Interface A 9 Contents...
