This topic describes the basic operation of Lawo VSC.

Starting the ApplicationLink to Starting the Application

Lawo VSC can be started in the usual manner for a macOS app. e.g. Select Lawo VSC from the Applications folder.

The first time you start the software, you will need to work through the first-time startup tasks (described earlier). On all subsequent startups, Lawo VSC loads the latest configuration.

When the application opens, the main Lawo VSC window (1) is in view. Here you can configure the audio devices and their streams.

Other functions, such as the 'Settings' dialog can be opened from the app menus (2). There is also a status menu (3) that can be opened from the macOS status area (as shown below).

Once the audio devices are configured, the main window can be hidden from view. This allows you to focus on your local audio applications during operation, once the streams are setup.

Closing the ApplicationLink to Closing the Application

Lawo VSC can be closed in one of the following ways: select Quit Lawo VSC from either the app or status menus (shown above) or use the keyboard shortcut (cmd + Q).

Depending on the Stop Audio Engine on Quit option (in the 'Settings → Advanced' dialog), Lawo VSC will either stop streaming when the application quits OR continue running as a background service (so that all existing streams and audio devices remain available). For more information about this option, please see Lawo VSC - Advanced Settings.

Lawo VSC Main WindowLink to Lawo VSC Main Window

The Lawo VSC window opens with a sidebar (on the left) and a main working area (on the right). If the window has been hidden from view, then use either the Show All option (in the app menu) or Show Main Window option (in the status menu) to bring it back into view.

The left-hand sidebar shows a list of the 'Audio Devices' that have been configured. You can use the + and - buttons at the bottom of this area to add or remove a device. Above the buttons is a status area that will show messages about the license and/or sync status if there is an issue to resolve.

The main working area shows the name of the selected device (in the title bar) plus the following information:

  • The number of Inputs and Outputs defined for the selected device.
  • The Sample Rate of the Audio Engine.
  • The name and status of the Receivers and Senders for the selected device.

The device name always starts with "Lawo VSC", but the second part of the name can be edited. This is defined, along with the number of inputs, outputs, receivers and senders, by the audio device configuration.

The sample rate is a global setting for Lawo VSC which can be changed from the 'Settings → General' dialog.

Interrogating the Receivers & SendersLink to Interrogating the Receivers & Senders

The following information is always displayed for each receiver and sender:

  • ID - indicates the number of the receiver or sender.
    The ID number is useful if there are multiple entries. For example, if a 64 input device has 8 x 8-channel receivers and you wish to check inputs 9-16, you will need to select receiver 2.
  • Status - indicates the status of the connected stream (for a receiver) or the outgoing stream (for a sender). Hover over the icon to reveal more information.
    If a receiver is not connected, then it is normal to see a yellow warning indicator. The warning will clear once a connection is made (providing that the stream subscription is successful).
  • Label - identifies the receiver or sender within the network. The labels are defined as part of the audio device configuration. They cannot be edited once the audio device is created.
  • Connected Source (shown for receivers) - shows the status and name of the connected stream (once a connection is made).

If you select a receiver or sender, then more information and functionality can be revealed by clicking on the show/hide side panel icon (in the top right-hand corner).

In each case, there are three pages of functions that are selected by clicking on the tabs: Channels, Receiving (or SDP) and Properties.

Receiver OperationsLink to Receiver Operations

When a receiver is selected, there are two pages of interest: Channels and Receiving. In the current release, the Properties page is empty and has no function.

The Channels page shows the individual audio channels of the selected receiver. From here you can:

  • Meter the audio arriving from the connected stream (if a connection is made).
  • Click on Listen to monitor the audio on the local playback device (defined in the 'Settings → General' dialog).

The Receiving page shows information about the connected stream (if a connection is made). If there is no stream connected, then the fields are empty. From here you can:

  • Setup a new streaming connection (using Select Stream).
  • Disconnect Stream (to remove an existing connection).
  • View Advanced Details & Statistics for the connected stream (for diagnostic purposes).

For more information, see Lawo VSC - Receiving Audio from the Network.

Sender OperationsLink to Sender Operations

When a sender is selected, all three pages are populated.

The Channels page shows the individual audio channels of the selected sender. From here you can:

  • Meter the audio carried by the outgoing stream.
  • Click on Listen to monitor the audio on the local playback device (defined in the 'Settings → General' dialog).

The SDP page shows the SDP data for the outgoing stream. This can be used to:

  • Check the contents of the SDP data.
  • Copy the SDP data to the clipboard (so that it can be used by another device/receiver).

The Properties page can be used to access the sender properties. From here you can:

  • Add Stream - opens the 'New Stream Sender' dialog (to create a new stream). This option is only available if there is no existing stream.
  • Enable Sender - enables (or disables) the stream. You can use this option to remove the stream from the network on a temporary basis.
  • Send Test Tone - sends test tone to each channel of the selected sender in sequence. So, tone appears on channel 1 for a few seconds, then on channel 2 and so on until all channels are tested. 
  • View Advanced Details & Statistics - opens a dialog with the stream details and statistics (for diagnostic purposes).
  • Remove Stream - deletes the stream. Click on Remove to confirm or Cancel to cancel the operation. Once the stream is removed, you can use Add Stream to configure a replacement.

For more information, see Lawo VSC - Sending Audio to the Network.

Status MessagesLink to Status Messages

If there is a licensing or sync issue to resolve, then a message appears in the status area (at the bottom of the 'Audio Devices' list). There are two message types:

  • Grace Mode - This message appears if you are running the licensed version of Lawo VSC and a valid license is not found.
    • To resolve the issue, either install a license or switch back to the Free version (as described in Lawo VSC - License Activation).
    • If the grace period expires before a license is found, then white noise is inserted into the audio.
  • No Sync - This message appears if a valid clock source is not found.

Once everything is ok, the status messages clear.

NICs Not FoundLink to NICs Not Found

The following message appears if one of the Network Interface Cards (NICs) is not found.

To resolve the issue, open the 'Settings → Streaming' dialog and choose a network interface for the NIC 1 (and NIC 2) fields.

The App MenuLink to The App Menu

When the main Lawo VSC window is in focus, the application's menu bar is visible. 

Click on Lawo VSC to access to the following options:

  • About Lawo VSC - opens a dialog with information about the app. From here, you can check the release version of Lawo VSC.
  • Settings - opens the 'Settings' dialog. From here, you can adjust all of the global settings for the app. For more information, please see Lawo VSC - Settings.
  • Services - refers to services for the macOS. There is nothing specific to Lawo VSC here.
  • Hide Lawo VSC, Hide Others and Show All - these options can be used to show or hide the main Lawo VSC window. 
  • Quit Lawo VSC - this option will close the application. What happens to the streams is dependent on the Stop Audio Engine on Quit option. For more information, please see Lawo VSC - Advanced Settings.

The other menus (Edit, View, Window and Help) offer the usual options for a macOS app. There is nothing specific to Lawo VSC here.

The Status MenuLink to The Status Menu

The Lawo VSC status menu can be opened from the macOS status area (as shown below).

The first few fields show the status of the Lawo VSC services.

Audio DriverLink to Audio Driver

The Audio Driver is always connected; it cannot be disconnected. During normal operation, the status shows as "connected" with a green flag. 

The Uninstall option can be used to remove the audio driver. Note that this closes Lawo VSC (as the driver is mandatory).

Audio EngineLink to Audio Engine

The Audio Engine is always connected; it cannot be disconnected. During normal operation, the status shows as "connected" with a green flag.

In the event of an issue, there are two options that can be used to perform a restart:

  • Restart - restarts the Audio Engine and loads the latest configuration.
  • Reset & Restart - resets (clears) the configuration and then restarts the Audio Engine. Note that if you choose this option, then all audio devices are removed.

HOME ServiceLink to HOME Service

The HOME Service is always connected; it cannot be disconnected. During normal operation, the status shows as "running" with a green flag.

There are no further options for the HOME service (as the service is always running). If you wish to connect or disconnect a HOME system, then this can be done from the 'Settings → HOME' dialog.

SyncLink to Sync

The Sync area shows the status of the incoming sync signal. If a valid clock signal is detected, then the status shows the type of signal (e.g. PTP) with a green flag.

The Details option can be used to open a dialog with more information about the clock signal. This is refreshed every 5 seconds. An example for PTP is shown below.

Other FunctionsLink to Other Functions

The Show and Hide Main Window options can be used to show or hide the main Lawo VSC window.

The Quit Lawo VSC option provides another way to close the application.