VST Bridge

Essentials

The Audiotool VST Bridge connects the web-based DAW to VST3 plugins on your computer, so instruments and effects you have installed locally can run inside Audiotool Studio while you work in the browser.

It is a native companion app that runs alongside the browser and carries audio and plugin processing on your machine. Spitfire LABS is a typical example; other VST3 plugins work the same way.

Download & Install

  1. Open the Hub and open the VST Bridge page.

  2. Download VST Bridge for your platform.

  3. Install the VST Bridge.

    • Windows

      • Double-click the downloaded file.

    • macOS

      • Double-click the downloaded file.

    • Linux

      • Download and extract the zip file containing the AppImage

      • Mark file as executable: chmod +x <vst-bridge-file>.AppImage

      • Launch the app: ./<vst-bridge-file>.AppImage

Use VST Bridge

  1. In your project, drag the VST Bridge device from the Device Browser into the timeline or studio.

  2. On the device, select the VST3 plugin you want to connect.

  3. Open to show the VST plugin window.

  4. Save to store any VST3 change. Even collaborations are possible when all producers have the same plugin installed.

Note: When you add a plugin to the folder, in the VST Bridge app, click Re-scan to “discover” the new plugin.

Use Spitfire LABS

Note: Spitfire LABS is not supported on Linux.

  1. Download and install the Spitfire LABS plugin (not “Splice Instruments”)

  2. Restart the VST Bridge

  3. Open an Audiotool DAW session

  4. Drag the Spitfire LABS device from the Device Browser into your timeline

  5. Double click the LABs device to open the LABs plugin window.

Connecting

The DAW will generally inform you in case any action is required. You can even start the VST Bridge from the DAW with the “Connect” button in the bottom right corner.

The VST Bridge is ready to connect when it looks like this:

../_images/vst-bridge-ready-to-connect.webp

A session in the Audiotool DAW will try to connect to the VST Bridge on startup. If you already have the DAW open, reload the tab.

If the connection is successful, you can see the version number in bottom right.

And the VST Bridge will look like this:

../_images/vst-bridge-connected-app.webp

Note that an instance of the VST Bridge can only connect to one session at a time.

Troubleshooting

Latency Issues

You can potentially reduce general recording- and input latency by choosing the correct settings in the Host, Device and Blocksize dropdowns. The final latency is dependent on the Actual Blocksize shown in the VST Bridge UI. The lowest and best latency is achieved with a block size of 128.

../_images/vst-bridge-connected-app.webp

Audio recording latency can be worse with the VST Bridge than without, even with ideal block size and input latency correction. We’re working on this issue.

VST Bridge not detected

The VST Bridge can connect to at most one Audiotool DAW session at a time, and the DAW will only attempt connection on startup. If restarting the VST Bridge and the DAW doesn’t help, please submit a bug report!

Linux Audio Issues

The VST Bridge currently requires Jack, ALSA, or PulseAudio to be installed. The best latency is achieved with Jack. If you use PipeWire, you can use wrappers such as pw-jack or pipewire-alsa.

LABs plugin state synchronization

The LABs plugin state is synchronized between all clients in a multi-user session. However, the plugin is currently only audible on clients that have a connected VST Bridge with the LABs plugin installed.

This will be addressed in future updates - stay tuned!