SOUND DEVICES ASTRAL A20-NEXUS (01) PDF Document

To set up your SOUND DEVICES ASTRAL A20-NEXUS as a standalone receiver, please follow these steps:

1. Connect a 10-18V DC power source to either or both TA4-M DC inputs. Alternatively, connect PoE+ to Ethernet port 1.

2. Connect suitable passive, bias-powered, or smart antennas to either the front or rear BNC A and B antenna ports.

3. If using NexLink to control and monitor A20 transmitters, connect 2.4 GHz antennas to both rear panel 2.4 GHz SMA ports.

4. Connect required rear panel audio outputs (Analog, AES, and/or Dante) from the Nexus to external devices.

5. Connect headphones to the front panel 3.5 mm headphone output.

6. Power Up. Press the front panel triangle button to power up. Press and hold to power down. When powered up for the very first time, receiver channels 1-8 are displayed. This view is called the 8RX View. All RX channels default to Off.

To set the country on your SOUND DEVICES ASTRAL A20-NEXUS, follow these steps:

1. Press the triangle button to display the Main Menu.

2. Tap the System icon to enter the System menu.

3. Ensure Country is set to the country that you are in.

The Country setting is important because it determines which Tuning Bands and RF frequencies are legally unrestricted and available for selection in the A20-Nexus. If using A20 transmitters, make sure that the A20-Remote app they are paired to is also set to the same country.

1. From the Main Menu, select Audio Out.

2. From the Audio Output menu, select the audio output routing options. Here you can configure settings such as Sync Ref, Sample Rate, D-Sub outputs, HP Out, and Tone settings.

1. Use the triangle button to return to the Main menu.

2. Tap the RF icon in screen 2 to access the RF menu.

3. Select Front or Rear antennas by tapping the button at the bottom of screen 2. When ‘Rear’ is displayed, the rear antennas are selected. When ‘Front’ is displayed, the front antennas are selected.

If your antennas require bias-power, tap the A and B antenna gear icons in the RF Menu to display A and B antenna settings respectively. Set both their Power (Bias) settings to On. The antenna icons will show a lightning bolt icon next to them when bias power is enabled.

Pairing adds A20 transmitters to the A20-Nexus TX List, which is an inventory of available transmitters for wireless remote-control via NexLink.

To pair an A20 transmitter:

1. From the Main Menu, tap the TX List icon.

2. Ensure the A20 transmitter has a charged battery or batteries installed.

3. Connect its USB-C port to the A20-Nexus USB-A port.

The A20 transmitter will appear in the TX List after a few seconds. The A20-Nexus will then automatically establish a NexLink connection between the transmitter and the next available receiver channel. This can take up to a minute. Once the connection is established, the NexLink RSSI icon is displayed in the TX List.

No, A10-TX transmitters cannot be paired or NexLinked with the SOUND DEVICES ASTRAL A20-NEXUS. To tune to an A10-TX, you must manually set the RF frequency, Modulation, and Privacy of the Nexus receive channel to the same settings as the A10-TX transmitter.

From the TX List, rotate the front panel knob to highlight a receiver channel. Then, press the knob to jump to its 1RX View. From this view, the receiver and its NexLinked transmitter can be configured and monitored.

In the 1RX View for the specific transmitter, ensure the transmitter is within NexLink range by checking that the NexLink RSSI indicator in the leftmost screen shows good signal strength.

If the A20 transmitter is not already on, you can power it on remotely from the 1RX View. In the 1RX View for the desired channel, tap the Power ON button in screen 3.

1. Press the triangle button to access the Main Menu, then tap the RTSA icon.

2. In the RTSA view, rotate the Control knob (or tap the top half of the plot) to move the blue vertical frequency marker to a clean frequency, which is a location with low background RF noise.

3. Press the Control knob to display the ‘Assign Frequency To:’ list.

4. Tap the desired receiver channel (e.g., RX1) to assign the clean frequency to it. The frequency is automatically pushed to the transmitter, and its RF signal will appear in the trace.

Alternatively, you can select ‘Auto Assign All’ at the top of the list to automatically deploy clean frequencies to all active channels.

Before assigning frequencies, it is highly recommended to perform a scan of the local RF environment using Scan Mode to identify and choose a clear Filter Range to apply to the Tuning Band.

1. While in the RTSA view, tap the orange number below the transmitter signal to jump to the 1RX View for that channel number.

2. Tap the Gain button.

3. Rotate the Control knob to bring up the gain until you see an audio signal from the lavalier microphone connected to the A20 transmitter.

4. Press the Control knob to store the gain value.

Connect your headphones to the 3.5 mm front panel jack. Rotate the Control knob clockwise to increase the headphone (HP) gain and listen to the audio.