A precision audio signal generator for iOS with a retro hardware aesthetic.
- Tone generation — Sine, Square, Sawtooth, and Triangle waveforms from 10 Hz to 20 kHz
- Noise generation — White and Pink noise
- PolyBLEP anti-aliasing — Band-limited square, sawtooth, and triangle waves for clean output at all frequencies
- Jogwheel — Rotary frequency control with configurable step increments (0.1, 1, 10, 100 Hz) and frequency snapping
- Direct frequency input — Tap the display readout to type an exact frequency via calculator-style keypad
- CRT display — Real-time animated waveform visualization with frequency readout, musical note detection, and volume indicator
- Crossfade switching — Seamless transitions between waveform types with no pops or clicks
- Retro UI — Inspired by 1970s handheld electronics, TI calculators, and Teenage Engineering
- iOS 17+
- Xcode 16+
Open SignalGenerator.xcodeproj in Xcode, select your target device, and run.
Built with SwiftUI and AVAudioEngine. The audio engine uses an AVAudioSourceNode render callback with PolyBLEP anti-aliasing for alias-free synthesis — lowest possible latency with no intermediate buffers.