Selecting an audio source
Choose different audio sources for a channel using the Admin panel.
Select your audio sources from connected video source, as well as from the dedicated analog audio input ports. The USB port on the rear panel accepts a USB microphone (UAC).
Linked ports
- On Pearl Nano, the XLR audio ports and the RCA audio ports are linked.
Selecting an audio device for the channel:
Using a web browser on the admin computer, go to the IP address of your Pearl Nano and log in,
From the Channel menu, select your channel (i.e. Auto) and click Layout. The custom channel layout editor page opens.
Check the audio source that you want to use for the layout and click Save.
(Optional) Adjust the gain for an audio input source, select the input port from the Inputs menu and adjust the amount of gain on the configuration page for the audio input port. Click Save when you're done.
Connecting microphones to the XLR line level inputs
The XLR analog audio input ports on Pearl Nano are professional line level inputs rated at + 4.0 dBu up to 12.3 V RMS, (+24 dBu). You can't connect microphones directly to the XLR ports because the microphone signal is too low.
If you want to connect microphones to the line-level XLR ports on the Pearl Nano, you must use an external preamp and boost the mic level signal to the appropriate line level before connecting it to the XLR port.
Configure audio ports for stereo or mono
Using the Admin panel, you can configure ports to function as a stereo pair (left/right) or as separate mono ports.
Pearl Nano
The two XLR professional line-level inputs are configured as a stereo pair by default: XLR 1 (left) and XLR 2 (right).
Configure audio ports as stereo or mono using the Admin panel
Log in to the Admin panel as admin.
Open the configuration page from the Inputs menu:
Pearl Nano: click XLR/RCA Audio. The XLR/RCA Audio configuration page opens.
Do one of the following.
To make the ports function as a stereo pair, check Stereo pair and click Apply.
To make the ports function as separate mono ports, uncheck Stereo pair and click Apply.
When mono is selected, two sets of parameters and two audio VU meters appear in the interface - one for each audio input port on the Pearl Nano. Parameters that are listed only once apply to both ports.
Configure audio ports as stereo or mono using the Pearl Nano front screen
Repeatedly press the left arrow key on the control interface until the Menu screen displays.
Use the arrow and check mark keys to select Inputs. Then from the Inputs screen, select XLR/RCA Audio to open the XLR/RCA Audio screen.
Highlight Stereo pair and press the check mark key to toggle the switch on or off.
Assign audio sources to an input
Some audio input ports share internal audio processing resources in the Pearl Nano. These shared audio sources appear in the same configuration menus in the Admin panel and appear under the same audio input label in the user interfaces.
The audio sources that share resources are:
Pearl Nano
XLR 1 and XLR 2 (left and right ports, respectively)
RCA (left and right ports)
Both the XLR (left/right) and RCA (left/right) audio sources appear under the label XLR/RCA Audio. You can assign one or both audio sources to XLR/RCA Audio. Choosing one audio source for the shared input disables the other audio source. This means that when you select XLR/RCA Audio as the audio source using the custom layout editor, only the audio source you assign to XLR/RCA Audio is used. Both audio sources are assigned by default.
To avoid unwanted signal noise on the RCA ports, we recommend adding no more than 12dB of gain when RCA or XLR+RCA is selected.
Assign the audio source to an input using the Admin panel
- Log in to the Admin panel as admin.
- From the Inputs menu, select the shared audio source. The audio configuration page opens.
- From the Input menu, select the audio source and click Apply.
Choose XLR or RCA audio for analog inputs using the front screen
- Press the left arrow key repeatedly on the control interface until the Menu screen displays.
- Use the arrow and check mark keys to select Inputs. Then from the Inputs screen, select XLR/RCA Audio to open the XLR/RCA Audio screen.
- From the XLR/RCA Audio screen, highlight Input and press the check mark key to display options.
- Highlight the option you want (XLR, RCA, or XLR/RCA), then press the check mark to select and return to the previous screen. To return to the previous screen without making a selection, press the left arrow key.
Adjust audio gain and delay
Pearl Nanos do not introduce audio delay and have near-zero latency when capturing. However, other external factors can cause audio to become de-synchronized, such as the length of audio cables or the configuration of your equipment. The audio delay feature helps you adjust audio coming from external sources so that your video and audio sources are synchronized when captured, streamed, and recorded.
You can apply from -300 ms to +300 ms of delay to any audio source using the Admin panel or Pearl Nano's front screen. By default, there's 0 ms of delay applied to audio sources.
The analog audio input ports on Pearl Nano are calibrated for +4.0 dBu XLR or -10.0 dBV RCA audio signals and provide moderate to significant signal headroom. For the analog audio inputs, you can add up to +30 dB of gain.
Microphones typically have low audio signals (less than -30 dBu) and are not supported directly as inputs to Pearl Nano. Use an audio mixing board or preamp to amplify microphones and supply the appropriate line level input.
Adjusting the Input Gain for an analog audio source affects the volume for that audio source in recordings, streamed output, video output ports, and in the headphone jack. Be aware that excessive amounts of gain can increase the perception of any noise that may be present in the audio signal.
If the gain of your analog audio signal needs adjustment, connect your headphones and use the VU meters to monitor the audio level while you add some gain. As a rule, each 10 dB of gain doubles the perceived loudness of the audio signal.
This table offers some guidelines for adjusting the gain at the audio input port of Pearl Nano for common types of audio input devices. You should 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.
Table 22 Audio input port gains 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. |
| RCA1 | Nominal | |
| Professional mixer | XLR | Nominal |
| RCA1 | Not recommended. | |
| USB microphone | USB | Nominal |
| Dynamic, condenser, or electret microphones | XLR | Not recommended. To connect microphones to the pro line level XLR inputs, you must use an external preamp to boost the microphone signal enough to provide the proper line level signal at the XLR input port, |
1 To avoid unwanted signal noise on the RCA ports, we recommend adding no more than 12dB of gain to the RCA port or when XLR/RCA is used.
Ensure the audio input source is connected to an analog audio input port on Pearl Nano before proceeding.
Adjust the gain and delay for an audio source using the Admin panel
- Log in to the Admin panel as admin.
- From the Inputs menu, select an audio source. The audio configuration page for the audio source opens.
- In the Input Gain field, select the amount of gain to apply to the audio source.
- In the Audio delay field, enter a value between 300 and -300 ms. A positive value adds delay to the audio signal. A negative value adjusts the audio to start earlier.
- Click Apply.
Adjust the gain and delay for an audio source using the front screen
- Repeatedly press the left arrow key on the control interface until the Menu screen displays.
- Use the arrow and check mark keys to select Inputs. Then on the Inputs screen, select XLR/RCA Audio to open the XLR/RCA Audio screen.
- To adjust audio delay from the XLR/RCA Audio screen, highlight Audio delay and press the check mark key to display options.
- Highlight the amount of delay you want using the up and down arrow keys, then press the check mark key to select and return to the previous screen. To return to the previous screen without making a selection, press the left arrow key.
- To adjust the gain from the XLR/RCA Audio screen, highlight Gain and press the check mark key to display options.
- Highlight the amount of delay you want using the up and down arrow keys, then press the check mark key to select and return to the previous screen. To return to the previous screen without making a selection, press the left arrow key.
Mute audio
You can mute any audio input port using the Admin panel. For analog audio ports that are configured as mono inputs, you can mute each port separately.
Some audio input ports share internal audio processing resources in the Pearl Nano. Muting an audio input that shares internal resources mutes all the associated audio sources. The following table lists the audio input ports that share internal processing and the results of applying mute.
Table 23 Muting audio inputs that share resources
| Device | Audio input (Admin panel) | Shared audio input resources | Results |
|---|---|---|---|
| Pearl Nano | XLR/RCA Audio | XLR (left/right) RCA (left/right) | In stereo mode: Both XLR ports (left and right) are muted. Both RCA ports (left and right) are muted |
| In mono mode (XLR/RCA audio Left muted): Both the XLR 1 (left) and RCA left ports are muted. The XLR 2 (right) and RCA right ports are not muted. | |||
| **In mono mode (XLR/RCA audio Right muted):**Both the XLR 2 (right) and RCA right ports are muted. The XLR 1 (left) and RCA left ports are not muted. |
Mute an audio source using the admin panel
- Log in to the Admin panel as admin.
- From the Inputs menu, select an audio source. The audio configuration page for the audio source opens.
- Check Mute to mute the audio source or uncheck Mute if you no longer want the audio source muted, then click Apply.
Mute an audio source using the front screen
Press the left arrow key repeatedly on the control interface until the Menu screen displays.
Use the arrow and check mark keys to select Inputs. Then from the Inputs screen, select XLR/RCA Audio to open the XLR/RCA Audio screen.
From the XLR/RCA Audio screen, press the down arrow key repeatedly until Mute appears on screen and is highlighted.
Press the check mark key to toggle the switch on or off.