Getting Started
Requirements
- iPhone or iPad with iOS 17.0 or later
- USB audio interface (class-compliant)
- Lightning to USB or USB-C adapter (if needed)
- Audio cables for your equipment
First Launch
- Install SonicDNA Collector from the App Store
- Grant microphone permission when prompted
- Connect your audio interface
- The app will automatically detect the interface
Interface Overview
Main Screen
┌─────────────────────────────────┐ │ [🎵] SonicDNA [?] [📁] │ ← Navigation ├─────────────────────────────────┤ │ [🎤 Input Device] [🔊 Output] │ ← Device Selection │ [📋 Device Name Input ] │ ← Equipment Name ├─────────────────────────────────┤ │ OUTPUT ████████░░░░ -12dB [C]│ ← Output VU │ ▁▂▃▄▅▆▇█▇▆▅▄▃▂▁ │ ← Output Spectrum ├─────────────────────────────────┤ │ INPUT ████████░░░░ -18dB [C]│ ← Input VU │ ▁▂▃▄▅▆▇█▇▆▅▄▃▂▁ │ ← Input Spectrum ├─────────────────────────────────┤ │ DEBUG CONSOLE │ │ 06:30:15.123 Engine started │ ← Real-time Logs │ 06:30:15.456 Input: ZOOM AMS │ ├─────────────────────────────────┤ │ ● Ready 96.0 kHz │ ← Status ├─────────────────────────────────┤ │ [5 STEPS] [⏺] [0dBFS] │ ← Controls │ Staircase │ └─────────────────────────────────┘
Controls
| Control | Function |
|---|---|
| 5 STEPS / 11 STEPS | Select gain staircase mode |
| Record Button | Start/stop recording |
| 0dBFS | Play/stop 1kHz test tone |
| [?] | Help screen |
| [📁] | Recordings library |
Indicators
| Indicator | Meaning |
|---|---|
| Green bar | Safe level |
| Yellow bar | High level (caution) |
| Red bar | Near clipping |
| [C] Red | Clipping detected! |
Equipment Setup
Signal Flow
┌──────────┐ ┌────────────┐ ┌─────────────┐ ┌──────────┐
│ iPhone │───▶│ Audio I/F │───▶│ Equipment │───▶│ Audio I/F│───▶ iPhone
│ Output │ │ Output │ │ Under │ │ Input │ Input
└──────────┘ └────────────┘ │ Test │ └──────────┘
└─────────────┘
Connection Steps
- Connect Audio Interface
- Use appropriate adapter for your device
- Wait for iOS to recognize the interface
- Connect Equipment
- Audio interface output → Equipment input
- Equipment output → Audio interface input
- Verify in App
- Check that input/output devices are detected
- Device names appear in the header
Gain Calibration
Using the Test Tone
Warning: The 0dBFS test tone is very loud!
- Lower your monitor volume first
- Tap the 0dBFS button
- Confirm the warning dialog
- Observe the OUTPUT meter (should show 0dB)
- Adjust equipment input gain
- Observe the INPUT meter
- Aim for -18dB to -12dB average
- Tap 0dBFS again to stop
Avoiding Clipping
- INPUT clipping (red C on input) = Hardware damage risk!
- Reduce audio interface gain immediately
- Check equipment output level
- OUTPUT clipping (red C on output) = Normal for test tone
- 0dBFS signal is full digital scale
Recording
Staircase Recording
The staircase recording plays multiple sweeps at progressively higher levels:
5 Steps Mode (Recommended)
- -30dB, -24dB, -18dB, -12dB, -6dB
- Total time: ~35 seconds
- Good for typical measurements
11 Steps Mode (Comprehensive)
- -100dB to 0dB in 10dB steps
- Total time: ~77 seconds
- Full dynamic range analysis
Recording Process
- Enter equipment name (e.g., "Neve 1073")
- Select step count
- Tap the red record button
- Wait for completion
- Find recording in library
Output Files
Each session creates a folder containing:
GainStaircase_2026-01-25T15-30-00/ ├── Sweep_-30dB.wav ├── Sweep_-24dB.wav ├── Sweep_-18dB.wav ├── Sweep_-12dB.wav ├── Sweep_-6dB.wav └── metadata.json
Analysis
Built-in Analysis
Navigate to Recordings → Select a session → Analysis
Available measurements:
- Frequency Response - Plot of magnitude vs frequency
- THD - Total Harmonic Distortion at each level
- Harmonics - Individual harmonic levels
Python Analysis Toolkit
For advanced analysis, use the included Python toolkit:
cd analysis/
python -m sonicdna analyze /path/to/session/Features:
- Impulse response extraction
- Detailed frequency response plots
- THD+N measurement
- Export to various formats
Troubleshooting
No Audio Interface Detected
- Check physical connection
- Try different USB port/adapter
- Restart the app
- Check iOS Settings → Privacy → Microphone
No Input Signal
- Verify cable connections
- Check equipment output level
- Ensure interface gain is not at minimum
- Check interface phantom power if needed
Clipping During Recording
- Reduce audio interface input gain
- Lower equipment output level
- Use a lower staircase range
App Crashes
- Close other audio apps
- Restart the app
- If persistent, reinstall the app
Tips for Best Results
- Use short cables - Minimize interference
- Disable iPhone sounds - Silent mode recommended
- Consistent levels - Don't adjust during recording
- Name your sessions - Easy organization
- Multiple takes - For critical measurements