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Aura8ip / Jan 2012
A u r a 8 i p P r o G U I
Output Metering
Like the Input metering, the Output metering is sample-accurate, peak
reading, and is calibrated in dBFS. By observing the difference between
the consistency of the Input and Output levels the effects of processing
are readily apparent.
Note also that because the Output Meters are reading the peak levels
of audio which has been processed and probably also peak limited, there
is no maximum level constraint like there is on the Input side of the pro-
cessor. In other words, the effects of processing have made the maximum
peak levels ‘known’ and therefore the Output meters may safely indicate
all the way up to 0dBFS.
While a 0dBFS output level is certainly possible, it may not be practical
from the standpoint that we do not know what the behavior of the device
following the Aura8ip is going to be, and whether it has enough headroom.
Our experience is that it is safe to set the digital output levels up to around
-3dBFS without incurring any unexpected distortion or other issue in the
equipment coming afterwards.
One additional thought about Output levels, if we may … when feeding audio
codecs it is best to keep their maximum Input level at -3dBFs or even slightly lower.
The reason for this is that when the codec removes energy from the audio (which it
must do in order to encode the audio) the peak audio levels inside the codec algo-
rithm increase because information has been removed, information that was required
in order to maintain the original peak levels. Now, the designers of the codec may
have accounted for this effect, or they may not. We do not know for sure. Therefore
the best thing to do is run the codec’s input levels a little on the light side, perhaps
between -6dBFS and -3dBFS, just to be safe.
Sidebar Region
To the right of the OUTPUT METERING column is a vertical row of
seven special buttons. Each button has been designed as an entry point
into a dialog designed to help the end user get the most functionality out
of the product.
Preset
When this button is left-clicked, a Windows style dialog opens. The
Pro GUI must be online to the processor for the window to display the list
of presets installed on the Aura8ip hardware.
The folder called
Aura8ip
represents the hardware itself and the presets
stored there. Other folders,
favorites
,
Factory Presets
, etc. can only be
seen within the Library dialog, covered later.
The appearance of the window that opens when the Preset button is
pressed is shown on the next page.
