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FM-531HD / May 2013
F M - 5 3 1 H D P R O G U I
Multiband AGC Controls
AGC Drive
The AGC Drive control adjusts the amount of signal into the AGC/Compressor,
primarily determining the amount of compression that can be achieved. Driving harder
(higher numbers) results in a more consistent on air sound, with an increased capabil‑
ity to pull up low passages in program material. Less drive creates a more “gentle” on
air sound and has less capability to bring up low passages.
The AGC Drive control simultaneously adjusts the sum and difference channels.
The range of this control is ‑12.0dB to +6.0dB.
Gated Mode
The Gated Mode controls determine how the AGC behaves in the absence of audio.
When Ooze is selected and the audio input falls below the AGC Gate Threshold,
rather than the gains of the bands “holding” they will slowly return towards 0dB.
This setting may be useful for formats that contain material with very wide dynamic
range or for certain speech‑based formats where the “Gate Delay” setting may not be
appropriate.
When Hold is selected and the audio falls below the AGC Gate Threshold value
the gains of the five bands will “freeze” at their current values and will hold at those
values until audio is present that is above the AGC Gate Threshold. This prevents the
increasing of gain in the absence of audio which would likely increase background
noise.
AGC Gate Threshold
The AGC Gate Thresh control sets the audio level below which the audio gain re‑
duction values are held until audio returns. The control can be set to OFF or adjusted
over the range of ‑79.0dB to ‑20.0dB.
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...
