Cepstrum
Spectrum Analyzer & dB Meter
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
See what you hear. Find the hum, measure the loudness, prove the difference — a real-time spectrum analyzer and sound level meter that never leaves your iPhone.
That hum in your bedroom at night. The bass leaking through the wall. The "quiet" air purifier that isn't. Cepstrum shows you exactly what you're hearing — a live picture of sound, measured with nothing but your iPhone.
SEE THE NOISE, NOT JUST HEAR IT
A real-time spectrum from deep bass to the top of your hearing, with a sharpened spectrogram that turns tones into crisp lines. Point it at a mystery sound and get its fingerprint: the fridge hum at 50/60 Hz, the fan bearing whining at 4 kHz, the feedback frequency before it screams at your venue.
KNOW HOW LOUD IT REALLY IS
A proper sound level meter with A/C/Z weighting and Fast, Slow and Impulse response. Is the gym actually too loud? The restaurant? Your kid's headphones? Set the offset against a meter you trust and read real dB SPL — not a guess.
PROVE THE DIFFERENCE
Capture a measurement, overlay another, and read the change in decibels. Did the new windows cut the street noise? Is the replacement fan quieter than the old one? Before and after, one seat against another — the answer on screen, not in your head.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
- Improved measurement accuracy.
The developer, Tongkun Lan, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Tongkun Lan
- Size
- 9.8 MB
- Category
- Utilities
- Compatibility
Requires iOS 18.0 or later.
- iPhone
Requires iOS 18.0 or later. - iPad
Requires iPadOS 18.0 or later. - Mac
Requires macOS 15.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 2.0 or later.
- iPhone
- Languages
English and 5 more
- English, French, German, Japanese, Simplified Chinese, Spanish
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Cepstrum $4.99
- Copyright
- © Tongkun Lan
