Rocket Calibrator
Pocket synth prototype — real-time DSP on STM32H750
Prototype in development phase
Prototype in development phase
Rocket Calibrator is an ultra-portable pocket synth built for spontaneous music-making. It’s not a test instrument or signal generator — it’s a playful, expressive musical device designed to turn everyday moments into sound experiments. Still in early development, its final shape may change — but the goal is clear: a tiny synthesizer that’s fun, musical, and precise.
Think of it as a pocket music lab — one where melodies, rhythms, and sonic textures launch into orbit with the twist of a knob and the press of a button.
Powered by an STM32H750 (Cortex-M7 @ 480 MHz) and a Burr-Brown / TI audio DAC, Rocket Calibrator focuses on musical expression and real-time interaction. A high-stability TCXO ensures tuning accuracy, while a mini OLED display shows parameters, waveforms, and patterns. With 24 tactile keys and 2 encoders, it gives you a hands-on way to explore synthesis, harmony, and sound shaping.
In a single synth, pitch differences from clock drift are usually inaudible. But when two or more devices jam together — each with its own clock — even small ppm errors become beating or slow phase drift. You can learn more about beating in acoustics on Wikipedia.
A TCXO (Temperature Compensated Crystal Oscillator) keeps frequency stable across temperature and time — ensuring your synth stays in tune and in sync with others, whether you’re playing in a warm studio or outdoors on a cold evening.
Spec: ±0.5% (5000 ppm)
Drift @ 10 kHz: ±50 Hz
Max. difference between two units: ≈ 100 Hz
Clearly out of tune
Spec: ±25 ppm
Drift @ 10 kHz: ±0.25 Hz
Max. difference between two units: ≈ 0.5 Hz
Slow audible beating — noticeable over time
Spec: ±2 ppm
Drift @ 10 kHz: ±0.02 Hz
Max. difference between two units: ≤ 0.04 Hz
Virtually no beating — perfect long-term sync
* At 10 kHz pitch reference (≈C9), 1 Hz difference equals 0.017 cents — too small to hear as “out of tune” but audible as amplitude beating if signals mix.
With a TCXO’s ±2 ppm stability, Rocket Calibrator keeps its oscillators aligned. That means consistent tuning wherever you play — no slow drift, no phase wobble, just clean harmony.
Designed for true portability, it runs on USB-C power and supports a Li-ion battery, so you can make music at your desk, on the train, or outdoors. Compact, lightweight, and efficient — your music companion on the move.
Like all Noise Sculptors prototype projects, Rocket Calibrator is open and experimental. Firmware and features will evolve, adding new synthesis modes and musical tools. What will stay the same is its mission: to put playful sound creation in your pocket.
* Prototype stage: specifications, features, and design are subject to change.
Rocket your pocket music into orbit — coming soon.