PedalScope
Distortion, decoded.
Every drive pedal shapes your signal in ways you can hear but can't quite name. PedalScope measures what the circuit actually does — and turns it into charts you can read, sounds you can compare, and words that make sense.
Coming soon to the Mac App StoreLaunching at $19.99, regular $29.99 · For macOS 26 and later · Requires an audio interface for hardware measurement · Simulation Mode works with none
Plug in. Click once. Meet your pedal.
- 1 — Loop it in. Interface output → pedal → interface input. Any USB audio interface works.
- 2 — Measure. One click captures a complete fingerprint — harmonics, clipping curve, compression, gain journey, chord behavior.
- 3 — Understand. See the clipping shape you've been hearing for years. Play the harmonics by themselves. Read a plain-language summary built strictly from the measurements.
The clipping shape you hear, drawn live.
Transfer curves with real hysteresis. Harmonic recipes with even and odd orders separated. Distortion mapped across frequency and level, so you can watch a pedal clean up as you play softer. This is what "warm," "aggressive," and "touch-sensitive" look like.
The transfer curve is the pedal's clipping shape drawn directly — steep where it's clean, flat where the clipper takes over, asymmetric where the warmth comes from.
The harmonic recipe, even and odd families separated — the difference between thick and sour, made visible.
Distortion mapped across every note and drive level — watch where a pedal cleans up, and where it never does.
Loudness-matched, so nothing wins by being louder.
Every comparison in PedalScope is matched to equal loudness — the trick your ears fall for is the first thing the app controls for. Solo the even harmonics. Listen to the intermodulation "mush" of a distorted chord by itself. A/B two pedals blind and find out what you actually prefer.
Listen for: The first seconds are nearly clean; from the middle onward the note grows hair as it pushes into the curve's bends — that arrival of grit, not a volume change, is what the ramp teaches.
Listen for: Under the two notes there's a rough, beating undergrowth that neither note explains — that's the intermodulation, isolated in the next player.
Listen for: Only the undergrowth remains: a dissonant, clattering chord of tones the pedal invented. Through a clean bypass this lane is near-silence — the products are made by the distortion, not the notes.
Made for people who own a soldering iron.
Define your pedal's controls, sweep a clipping-diode switch position by position, and overlay the results — mods become measurements, and measurements become figures you can post. Export everything as open JSON your Python scripts can read.
No pedal handy? Start in Simulation Mode.
Design a virtual drive circuit — threshold, symmetry, knee, filters — and measure it with the same tools. It's the fastest way to learn what every design choice does to your tone, and it works on a MacBook on the couch. See how it works →
How we know it's right.
Published methods (Farina / Novák synchronized swept-sine), validated against analytic ground truth in software and reference circuits in hardware. Built by a measurement scientist who teaches signal theory — and plays through a Rat he built himself. The full methods and credits are in the guide.
Private by construction.
Your measurements stay on your Mac. No account. No tracking. No analytics — not even on this website. The optional AI-worded summaries run entirely on-device and are always labeled. The whole privacy policy fits in a paragraph →