> For the complete documentation index, see [llms.txt](https://docs.acestudio.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.acestudio.ai/instruments/third-party-instruments.md).
# Third-Party Instruments
Load third-party VST3 and AU instrument plug-ins on Instrument Tracks in ACE Studio.
ACE Studio hosts third-party instrument plug-ins — synths, samplers, and sound libraries in **VST3** or **AU** format — right alongside its AI instruments. Load a plug-in from the **Plugins** tab of the [Instrument Library](/instruments/instrument-library.md), and the track becomes an **Instrument Track** that plays MIDI clips the way any DAW does.
***
### Supported formats
| Format | Windows | macOS |
| -------------------- | ------- | ----- |
| **VST3** | ✓ | ✓ |
| **AU** (Audio Units) | — | ✓ |
* Only **64-bit** plug-ins are supported.
* On Apple Silicon Macs, plug-ins run **natively**.
* ACE Studio fully scans the standard plug-in folders on its first launch and picks up changed files on later launches. For scan locations and how to re-scan, see [Preferences](/account-and-settings/preferences.md#plugins).
***
### Loading a plug-in
Open the Instrument Library and switch to the **Plugins** tab. On Windows the tab is labeled **VST Plugins**; on macOS it is **VST/AU Plugins**.
* **Vendor list** — the column on the left groups plug-ins by manufacturer, with a count next to each name. **All** is selected by default. Search and the Type filter apply within whichever vendor you pick.
* **Type** — filter by category, such as Synth or Sampler. Only VST3 plug-ins can be filtered this way.
* **VST3 / AU** — on macOS, switch between the two formats. ACE Studio remembers your choice.
Each card shows the plug-in image, its name, and a subtitle with the format, type, and vendor, such as *VST3, Synth, Xfer*. AU plug-ins show format and vendor only. Hover a long name to see it in full.
To load a plug-in, do one of the following:
* Drag the card onto an empty area of the canvas to create a new track.
* Drag the card onto a track header. Dropping onto an existing Instrument Track or AI Instrument Track replaces its sound source.
* Click the card, then click the canvas where you want the track.
To remove a plug-in from a track, right-click the track header and choose **Unload**.
***
### The Instrument Track
An Instrument Track is one of the sub-types of [MIDI Tracks](/project/arrangement-in-canvas/tracks/midi-tracks.md). It holds MIDI clips like a Vocal Track or an AI Instrument Track, but behaves differently in two ways:
* **Track header** — clicking the track picture opens the plug-in's own window instead of a sound source panel.
* **Piano Roll** — the Clip Editor shows standard MIDI editing. See [Velocity and MIDI CC](#velocity-and-midi-cc) below.
***
### The plug-in window
Click the track picture to open the plug-in window. ACE Studio adds a compact header above the plug-in's own interface:
* **Power** — turns the plug-in on or off.
* **Preset bar** — step through presets with < / >, see the current preset name, and open the preset menu. Presets work exactly as they do for effect plug-ins, including ACE Studio's `.acefxpreset` format and exporting in the plug-in's native format. See [Preset management](/project/mixing/effects/third-party-effects.md#preset-management).
* **MIDI Ch** — choose which MIDI channel the track sends to the plug-in.
***
### Velocity and MIDI CC
On an Instrument Track, the Piano Roll in the [Clip Editor](/project/arrangement-in-canvas/clips/clip-editor.md) has a controller lane below the notes. Use the selector at the bottom to choose what the lane shows:
* **Velocity** — one bar per note. Drag a bar to change how hard the note is played.
* **Pitch Bend** and **Modulation** — always available.
* **Other controllers** — the last slot is a menu. Pick any other MIDI CC, such as Sustain Pedal or Expression, to show it in the lane. Controllers that already have a fixed slot are greyed out in this menu.
#### Editing a controller curve
A controller curve is a series of anchor points joined by straight lines. When a lane has no anchors, it shows a dashed line at the controller's default value, and the plug-in receives that default.
With the **pointer** tool:
* Double-click anywhere in the lane to add an anchor, or click on the dashed line to add one there.
* Drag an anchor to move it.
* Double-click an anchor to delete it.
* Drag a box around several anchors to select them, then delete, copy, or paste them together.
With the **pen** tool, draw directly in the lane to create a continuous curve. In this mode only the line is shown, not the individual anchors.
Delete all anchors and the lane returns to the dashed default line.
---
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