Audio input ports

You can connect external audio devices like mixers directly to the dedicated audio input ports on Pearl-2s. Each Pearl-2 has a unique set of audio input ports.

Pearl-2

• Four XLR professional line-level inputs + 4.0 dBu up to 12.3 V RMS, (+24 dBu) that support balanced and unbalanced signals.

• One stereo pair RCA consumer line-level input (-10 dBV)

• Two USB video/audio ports

The four XLR audio inputs are configured as two stereo pairs by default: XLR A (left/right) and XLR B (left/right). 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.

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-2

The four XLR professional line-level inputs are configured as two stereo pairs by default: XLR A (left and right stereo pair) and XLR B (left and right stereo pair).

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-2: click Analog-A Audio for the XLR A ports or click Analog-B Audio for the XLR B ports. The configuration page for the audio ports 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-2. Parameters that are listed only once apply to both ports.

Assign audio sources to an input

Some audio input ports share internal audio processing resources in the Pearl-2. 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-2

• XLR-B (left and right ports)

• RCA (left and right ports)

Both the XLR-B (left/right) and RCA (left/right) audio sources appear under the label Analog-B Audio. You can assign one or both audio sources to Analog-B Audio. Choosing one audio source for the shared input disables the other audio source. This means that when you select Analog-B Audio as the audio source for a layout using the custom layout editor, only the audio source you assign to Analog-B 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, XLR+RCA (for Pearl-2)

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.

Adjust audio gain and delay

Pearl-2s 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. By default, there's 0 ms of delay applied to audio sources.

The analog audio input ports on Pearl-2 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-2. 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-2 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 28 Audio input port gains guidelines

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 B/RCA is used

Ensure the audio input source is connected to an analog audio input port on Pearl-2 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.

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-2. 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 29 Muting audio inputs that share resources

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.