Interpreting the gain reduction meter displays – Omnia Audio Omnia A/XE User Manual

Page 51

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over time. During normal operation, the indicators will have a dynamic “bounce” that you

will be able to get a feel for. Every now and then, you will see the processor react quickly

and show a larger amount of gain reduction. Notice that the response is very fast. This

action will recover very slowly, and return to “rest” with the main bar graph. This action will

be easily noticed on material that is very dynamic in texture. More on this below.
Another feature unique to Omnia A/XE is processor “Hold”. During brief pauses in audio,

the bar graphs will “freeze” and the GATE indicators will show the processor has entered

the Hold mode of the algorithm. This is most easily noticed when there is a “dry” voice

being processed.
The Input/Output level meters will change from green to red whenever the level exceeds

–12dBfs. The pills also change color on the Input/Output displays. In the dynamic process-

ing section the pills maintain the same color.

Note: The input and output levels are displayed relative to 0dB full scale (0dBfs). The 0 indicator on the

input/output bar graphs means that every available bit of signal level is being used at that time! There

is nothing more in the level department, except to create distortion… nasty sounding distortion!

Interpreting the Gain Reduction Meter Displays

Through careful observation of the processing bar graphs, significant information can be

acquired and analyzed about the audio signal on a moment-by-moment basis. The bar

shows the average value of the gain reduction, while the floating pill indicates the peak

value of gain reduction.

Since the processing algorithms in Omnia A/XE ‘adapt’ to the audio, it is capable of

performing many different processing functions at different times. The processing display

bar graphs may appear to indicate different kinds of operation with different program mate-

rial. This behavior is primarily based on dynamic range differences in the applied program

material. For program material that is already processed or lacking dynamic range, the bar

graphs will indicate differently than with material that possesses a high degree of dynamic

range. This is because audio signals that lack dynamic range, naturally or by previous

processing, will possess a lower peak to average ratio. Conversely, audio signals with a wide

dynamic range possess a higher peak to average ratio. The Omnia A/XE adapts differently

to each case.
For program material that has low dynamic range (or high RMS and low peak levels),

there will be more activity in the WB-AGC sections and less activity in the Multiband

Processors. This behavior is due to the WB-AGC response to high RMS energy, while the

Multiband section is reacting to lower peak energy. Sometimes the Multiband section may

not indicate any action at all. For Omnia A/XE, this is completely normal! Examples of

this behavior might be seen with heavily processed commercials or music, or with music

passages of sustained level. A good example is the Aerosmith CD “Pump.” This recording

has very little dynamic range. Try any up-tempo selection from this disk and you will see

the Wideband-AGC section make initial adjustments along with small amounts of limiting.

UNdErSTANdING ThE BAr GrAPhS ANd INdICATOrS | 45

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