User Manual
Pearl-2 User Guide                                      Selecting an audio source
l Admin Panel: On the audio input source's configuration page when you select the input source from 
the Inputs menu. You can also add the VU meter to appear on the video output ports, see Disable or 
enable audio and output port volume.
l Epiphan Live: See Monitor video and audio input sources
Selecting an audio source
You can choose the audio source for a channel using the Admin panel  and can have a mix of several different 
audio sources. Select your audio sources from connected video sources (SDI, HDMI, USB video/audio), as well 
as the XLR and RCA analog audio input ports.
There are:
l Four XLR professional line-level inputs + 4.0 dBu up to 12.3 V RMS, (+24 dBu) that support balanced 
and unbalanced signals. 
l One stereo pair RCA consumer line-level input (-10 dBV)
l Two USB video/audio ports
l Four HDMI ports
l Two SDI ports
The four XLR audio inputs are configured as two stereo pairs by default: XLR A (left/right) and XLR B 
(left/right), see Configure audio ports for stereo or mono. The XLR B audio ports and the RCA audio ports are 
linked. You can configure Pearl-2 to use both or just one of the audio sources using the Admin panel, see  
Assign audio sources to an input.
Audio for Auto channels are selected automatically.
This table offers some guidelines for adjusting the gain of the XLR and RCA analog audio input ports, as well as 
the USB ports. Add the suggested gain to the audio input to get an average  signal to register at a nominal level 
in the VU meter (i.e. where the green bars change to yellow). The actual amount of gain needed depends on 
the strength of the original audio signal. See  Adjust audio gain and delay for details. 
Table 7 Audio input port gain guidelines
Audio source
Input 
port
Gain
Mobile phone or other 
consumer line level device
XLR  Add +6 to +12 dB gain to the audio input port.
RCA Nominal
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