Unlimited Spectrum

A real-time audio and vibration analyser that is honest about what it can and cannot measure. Point it at anything that makes noise and watch it as a spectrum, a spectrogram, a waveform, a calibrated level meter, or a two-channel transfer function.

SIX VIEWS, TWO SENSORS

Spectrum analyser: real-time FFT from 512 to 32768 points, eleven windows, fractional-octave smoothing down to 1/48, peak hold, and markers that can name the nearest note.
Spectrogram: a scrolling waterfall with five colour maps. Changing the contrast re-maps the history you already have, so you can go back for something you nearly missed.
Oscilloscope: the raw waveform with triggering, hysteresis to reject noisy edges, and pre-trigger to show what led in.
Level meter: A, C, and Z weighting with Fast, Slow, and Impulse response, equivalent continuous level, and the L10, L50, and L90 statistics used in noise reports.
Transfer function: magnitude, phase, coherence, group delay, and impulse response, with a delay finder that locates the loudspeaker in samples, milliseconds, and metres.
Vibration on iPhone and iPad: the accelerometer weighted to ISO 2631-1, per-axis and vector-sum RMS, vibration dose value, and peak particle velocity.

MAKE SOUND TO MEASURE SOUND

A signal generator: sine, square, triangle, and sawtooth, white, pink, and brown noise, sweeps, and tone bursts.
Swept-sine room measurement: one button plays the sweep, computes the impulse response, and reports reverberation time (EDT, T20, T30) and clarity (C50, C80, D50, centre time), with the energy-time curve drawn underneath.
Reverberation time from a single clap, per band.

MEASURE PROPERLY

Octave down to 1/24-octave bands on the IEC 61260 definitions.
THD, THD+N, signal-to-noise ratio, SINAD, effective bits, and crest factor, shown only when the signal has a fundamental, because they mean nothing without one.
Noise exposure under NIOSH, OSHA, or ISO 1999. The reading always names its rule, and the panel will not compute a dose on an uncalibrated input.
NC, NR, and RC Mark II noise ratings, with the curves drawn over the spectrum and the band that set the rating named. That band is what to fix.
EBU R 128 loudness: momentary, short-term, and integrated LUFS, loudness range, and true peak.
Stereo correlation, balance, width, and a goniometer. Correlation predicts the complaint: a mix that sounds wide on headphones and disappears on a phone is one whose channels are cancelling.

HONEST NUMBERS, ALWAYS

Calibrate any microphone against a reference, with FRD correction files included. Until you do, readings are labelled dBFS instead of pretending to be SPL.
Where coherence is low the transfer function fades rather than pretending. A band whose decay never rose above the background shows no figure at all.
If a figure would be a guess, the app says so on screen and in every export.

KEEP THE RESULT

Record a session and re-analyse any moment of it.
Freeze reference traces and read the live difference in dB at the cursor.
Export CSV whose header names the window, FFT size, resolution, overlap, averaging, weighting, and calibration, and whose data is the raw bins rather than the display curve. Session logs with markers, a PDF report stating the full measurement settings, and WAV of anything you recorded.

Measurements keep running in the background and stay visible on the Lock Screen and in the Dynamic Island. Every chart can be heard, not just seen, through VoiceOver Audio Graphs.

ONE PURCHASE, EVERY DEVICE

One purchase covers Mac, iPhone, and iPad. Audio is analysed as it arrives, stored only when you press Record, and never transmitted. No account, no subscription, no in-app purchases, no ads, no analytics, and no tracking.