# baton-studio
[](https://crates.io/crates/baton-studio)
[](https://docs.rs/baton-studio)
[](https://opensource.org/licenses/MIT)
A Rust library for controlling the Presonus STUDIO1824c USB audio interface.
## Features
The Presonus STUDIO1824c is a professional USB audio interface that features:
- **18 input channels:**
- 8 analog input channels with mic/line/instrument preamps
- 2 digital S/PDIF input channels
- 8 digital ADAT input channels
- **18 DAW channels** (output channels from the computer's perspective)
- **24 output channels:**
- 8 analog line output channels
- 2 stereo headphone outputs (4 channels total)
- 2 Main output channels
- 2 digital S/PDIF output channels
- 8 digital ADAT output channels
- **Physical controls:**
- 48V phantom power button for mic inputs
- Main output mute button
- Main output mono button
- Instrument/line level switch for channels 1 and 2
## Mixer Architecture
The 1824c contains 9 separate internal mixes, each with stereo fader controls for all 36 input channels (18 physical inputs + 18 DAW channels):
- **Mix 1:** Main outputs (channels 1-2) + headphone output 1
- **Mix 2:** Line outputs 3-4 + headphone output 2
- **Mix 3:** Line outputs 5-6
- **Mix 4:** Line outputs 7-8
- **Mix 5:** S/PDIF digital outputs
- **Mix 6-9:** ADAT digital outputs (pairs 1-2, 3-4, 5-6, 7-8)
This library allows you to control:
- **72 input faders** (36 channels × 2 for left/right)
- **9 stereo output faders** (one per mix)
- **4 front panel buttons**
## Installation
Add this to your `Cargo.toml`:
```toml
[dependencies]
baton-studio = "0.1.0"
```
## Quick Start
```rust
use baton_studio::*;
use nusb::MaybeFuture;
use std::error::Error;
fn main() -> Result<(), Box<dyn Error>> {
// Find and open the device
let device = nusb::list_devices()
.wait()?
.find(|dev| dev.vendor_id() == 0x194f && dev.product_id() == 0x010d)
.ok_or(std::io::Error::new(
std::io::ErrorKind::NotFound,
"STUDIO1824c not found",
))?
.open()
.wait()?;
let mut command = Command::new();
let mut state = State::new();
// Enable phantom power
command.set_button(Button::Phantom, true).send(&device)?;
// Set input fader for channel 1 to -3dB
command
.set_input_fader(0, 0, Channel::Left, Value::DB(-3.0))
.send(&device)?;
// Set main output fader to -2.4dB
command.set_output_fader(0, Value::DB(-2.4)).send(&device)?;
// Poll current state and read meter values
state.poll(&device)?;
let mic_level = gain_to_db(state.mic[0]);
println!("Mic 1 level: {:.1} dBFS", mic_level);
Ok(())
}
```
## API Overview
### Commands
The `Command` struct allows you to control the device:
```rust
let mut command = Command::new();
// Control input faders (channel, mix, left/right, value)
command.set_input_fader(0, 0, Channel::Left, Value::DB(-6.0)).send(&device)?;
command.set_input_fader(0, 0, Channel::Right, Value::Unity).send(&device)?;
// Control output faders (mix, value)
command.set_output_fader(0, Value::DB(-3.0)).send(&device)?;
command.set_output_fader(1, Value::Muted).send(&device)?;
// Control buttons
command.set_button(Button::Phantom, true).send(&device)?;
command.set_button(Button::Mute, false).send(&device)?;
```
### State Monitoring
The `State` struct provides access to meter readings and button states:
```rust
let mut state = State::new();
state.poll(&device)?;
// Read input meters (dBFS values)
println!("Mic 1: {:.1} dBFS", gain_to_db(state.mic[0]));
println!("Line 1: {:.1} dBFS", gain_to_db(state.line[0]));
println!("DAW 1: {:.1} dBFS", gain_to_db(state.daw[0]));
// Read output meters
println!("Main L: {:.1} dBFS", gain_to_db(state.bus[0]));
// Read button states
println!("Phantom power: {}", state.phantom);
println!("Mute: {}", state.mute);
```
## Signal Flow
The signal routing works as follows:
```text
+-->Fader left--->\ /-->Line Output 1
|
...
|
+-->Fader left--->\ /-->ADAT Output 7
| |Stereo fader 9|
+-->Fader right-->/ \-->ADAT Output 8
```
Each of the 36 input channels can be routed to all 9 output mixes with independent left/right fader control.
## Hardware Requirements
- Presonus STUDIO1824c USB audio interface
- USB connection to your computer
- Proper USB permissions (you may need to run as root or configure udev rules on Linux)
## Examples
See the `examples/` directory for more complete usage examples:
## Testing
The library includes comprehensive tests:
```bash
# Run all tests (requires connected STUDIO1824c)
cargo test
```
## Platform Support
This library should work on any platform supported by the `nusb` crate:
- Linux
- macOS
## License
This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.
## Contributing
Contributions are welcome! Please feel free to submit a Pull Request.
## Acknowledgments
- Built on top of the excellent [`nusb`](https://crates.io/crates/nusb) USB library
- Inspired by the need for programmatic control of professional audio equipment