The Scenic application is designed to be used together with the X-AIR-Edit software, which controls the parameters of the XR18 mixer integrated into Scenic stations. The X-AIR-Edit software is used to adjust various parameters, such as input and output levels for each channel, as well as the assignment of digital audio tracks (audio connection matrix). The XR18 mixer is used to capture analog audio signals via XLR and 1⁄4" TRS connectors. Through analog-to-digital conversion performed by the XR18, these signals can then be retrieved by Scenic via a USB connection to the Scenic station computer.
Although there is already a detailed user manual for the Behringer XR18 mixer and the X-AIR-Edit application, the following parameter explanations will help you better understand their joint use with Scenic and highlight the most important settings. For more detailed information, refer to the Behringer XR18 user manual.
By default, X-Air-Edit is configured so that audio signals are transmitted to Scenic (USB) upstream of local parameters (levels, EQ, Gate, compression, etc.). Thus, EQ, compression, and noise reduction settings do not affect signals sent to a SIP partner, but only local outgoing signals.
¶ Useful Functions
- Setup Button: Allows you to connect Scenic to the XR18 if the connection does not happen automatically when opening X-AIR-Edit;
- The « Setup » window also lets you check the IP address assigned to each XR18 mixer connected to the local network, the IP address of the computer running X-Air-Edit, and the current firmware version. This information can be useful during a connection test, for example.
-
Input Tab: Each channel strip in X-AIR-Edit can be used in external mode (A/D)—corresponding to the physical (Mic/Line) inputs of the mixer—or internal (USB)—corresponding to the « XR18 Outputs » of Scenic. You cannot use both modes simultaneously on the same mixer channel;
-
Gate Tab: Echo is a common problem in telepresence contexts—where vocal or sound interaction between two locations can play an important role. To limit or eliminate this phenomenon, you must recognize its cause: the reinjection of an outgoing audio signal into a local input, which is then retransmitted to the output of the signal’s origin, with a delay, and so on.
In other words, the phenomenon is as follows: sound captured in one place is heard locally and transmitted to a remote location where it is also played through speakers; this signal is again captured by a microphone in the remote location and sent back to its origin; the signal is then played again by local speakers, with a delay of a few hundred milliseconds, resulting in the echo effect. A combination of strategies can help limit this phenomenon. One such strategy is the judicious use of a noise gate. The principle of the noise gate is to attenuate or completely eliminate (close the gate) the level of an audio signal when it is below a certain preset threshold (usually in dB): if the sound level is above this threshold, the signal remains unchanged (gate opens).
In X-AIR-Edit, this tool is found under the « Gate » tab;
Note: For effective noise gate operation, you must first consider microphone preamp levels and speaker amplification, as well as their respective placement. For more details, see the Audio Bleed Management section of the Technical Best Practices for Scenic Telepresence.
-
Suggested Parameters
-
Noise Gate: Enable or disable the gate;
-
Gate Mode: Gate closure ratio (dB reduction). The recommended setting is « Exp 4:1 »;
-
Threshold: Gate threshold. Start at -40dB. The voice sound level should be above the threshold to avoid attenuation, while ambient or unwanted sounds should remain below the threshold. If the threshold is too high, the voice will not exceed the gate threshold and the gate will remain closed. Adjust this parameter carefully for an adequate output signal;
-
GR: (Gain Reduction) Gate attenuation in decibels (dB). If the gate threshold is well adjusted, the red « GR » bar should be visible only when no one is speaking into the microphone;
-
Attack: Speed at which the gate is activated when the signal exceeds the threshold. The value should be close to 0 ms for a quick gate opening when speaking into the microphone.
-
-
Solo Buttons: Allow you to listen to one or more tracks with the XR18 mixer’s headphone output;
-
Save Button: Saves an X-AIR-Edit scene (use the « Save as scene » option). Scenes are saved locally at:
/home/scenicbox/X-AIR-Edit-Configs/Scenes. -
Load Button: Opens a previously saved X-AIR-Edit scene (use the « Load scene » option). A default scene for Scenic is available at:
/home/scenicbox/X-AIR-Edit-Configs/Scenes/scenic-station-discord.scn -
In/Out Button: Opens the XR18 connection matrix. Scenic uses the « USB Sends » tab matrix for the following sends:
-
« XR18 Input » to « XR18 Output »;
-
« XR18 Input » to remote station.
-
WARNING! Any changes inside this matrix could interfere with existing Scenic-XR18 routings.
By default, all assignments in the USB send matrix are in « Analog » mode. In this assignment mode, local parameter changes (output level, EQ, Gate, Comp, etc.), except for microphone input gain « Analog Input » (Mic Gain), will not affect the audio signal sent to SIP contacts.
Here is the default matrix for the « USB Sends » tab:
¶ Tutorial - Transmitting Audio Signals Between Scenic and the XR18
¶ Hardware Connection
- Connect a dynamic microphone (e.g., Shure SM58) to input 1 of the XR18 mixer at the back of the station. This mic will serve as the audio source;
- Connect the « Main L » and « Main R » outputs of the XR18 mixer to powered speakers or your main sound system—which usually includes a mixing console, amplification system, and passive speakers;
- Connect the Scenic station to your venue’s wide area network (internet). Plug the other end of your Ethernet cable into the WAN input at the back of the station.
¶ Starting the X-AIR-Edit Software
-
Launch X-AIR-Edit by clicking its icon in the Dock at the bottom of the left screen.
-
A small pop-up window appears, asking you to connect to the XR18 mixer. Click the « Connect » option;
-
Then click the « Mixer -> PC » option.
Keep X-AIR-Edit open at all times, as it is often useful to refer to during events. We suggest moving it to your right screen and using the left screen for Scenic.
-
In the X-AIR-Edit interface, select channel 1 (click the number 1), then click the « Input » tab;
-
Click the « A/D » button in the « Channel Source » section. This option assigns channel 1 to the physical input 1 of the XR18. Alternatively, the « USB » button assigns the channel to an audio source from Scenic;
-
Finally, confirm that the signal is being captured by your microphone by checking the peak meter for the corresponding channel.
¶ Creating an Audio Source from the XR18 in Scenic
-
Launch Scenic by clicking the Scenic icon in the Dock at the bottom center of the left screen;
-
In Scenic, click the « Sources » dropdown menu, then « Audio, » and choose « XR18 Input »;
-
Click the name of the newly created source to display its parameter panel on the right side of the screen. An audio source can represent one or more audio channels. In the parameter panel, you can change the number of channels you want to transmit and from which XR18 input channel. In this example, since only one microphone is connected to channel 1, the default options (one channel from XR18 channel 1) are suitable;
-
Once the audio source parameters are set, click the power button (green circle) to the left of the source—it will turn green—or the « Enabled » switch (Process On/Off) in the parameter panel;
-
You can now assign the audio source to your desired destination (SIP session partner, NDI® Output, or XR18 Output).
¶ Creating an Audio Destination to the XR18 in Scenic
-
In the « Destinations » dropdown menu, choose « Audio » then « XR18 Output »;
-
Click the name of the newly created destination in the matrix to display its parameter panel on the right side of the screen;
-
Click the « Output » tab in the parameter panel to display more options;
-
In the « Channel » option, indicate the starting channel from which incoming audio will be assigned. For example, if the audio source has 4 channels and you select channel 9 as the start, these channels will be distributed to channels 9, 10, 11, and 12 of X-AIR-Edit;
-
In the matrix, click the dark cell at the intersection of your audio source and the « XR18 Output » audio destination to assign one to the other. The cell will turn green.
-
The audio source is now redirected to the XR18 mixer. However, the source will not be audible if the input type for the corresponding channels in X-AIR-Edit is not set to capture signals from Scenic (USB) rather than from the physical inputs of the XR18 (A/D).
¶ Configuring X-AIR-Edit to Receive an Audio Source from Scenic
-
In X-AIR-Edit, click the strip corresponding to the starting channel of the XR18 Output in Scenic, as defined in step 4 of the previous section (e.g., 9), then click the « Input » tab;
-
Click the « USB » button in the « Channel Source » section. The channel now takes its audio source from Scenic and not from the corresponding physical input of the XR18 mixer;
Repeat steps 1 and 2 for each strip/channel. For example, if the « XR18 Output » in Scenic has 4 audio channels, repeat these steps for strips 10, 11, and 12 in X-AIR-Edit.
WARNING! Each channel of the XR18 should only be occupied by a single source: either a physical source (e.g., mic plugged into input 1) or a source from Scenic (e.g., XR18 Output destination assigned to starting channel 9).
- You should now see the audio signals from Scenic in the corresponding strips of the X-AIR-Edit interface. To hear these signals, make sure the faders for the relevant strips and the main output (LR) are at nominal level (0 dB).
