Checking the PA before doors open
Use sine and noise, left and right separately, to find a dead channel, a faulty cable or speakers that have been swapped. The signal fades in softly and stops as soon as a cable is pulled.
Music
iPhone & iPad
PA Check Signal generator and analyser for the soundcheck
PA Check is a signal generator and analyser for the soundcheck. Its two large dials for frequency and level can be used with one hand. Changes take effect at once and without clicks.
Download on the App Store
Free · one-time purchase “Analyser and Sweep” €19.99 · no subscription
Requires iOS 18.0
Screenshots
Use cases
Finding feedback
When a monitor starts to ring, the feedback finder shows the frequency in hertz and the matching third-octave band on a graphic equaliser.
Measuring a room
With pink noise you read the frequency response across 31 third-octave bands. The sweep draws the curve and marks peaks and dips. Several measurements can be compared and averaged, also with a measurement microphone on an audio interface.
Features
Free
€0
- Sine tone from 20 Hz to 20 kHz. Set the frequency with the dial, or double-tap it and type the value
- Pink and white noise
- Arrow buttons step in thirds of an octave, matching the bands of a graphic equaliser
- Output left, right or stereo, to find a dead channel
- Level shown in dBFS. The level stays below −12 dBFS and fades in softly
- The signal stops automatically when a cable is pulled or a call comes in. The screen stays on while the signal is running
One-time purchase “Analyser and Sweep”
€19.99
- Third-octave analyser with 31 bands from 20 Hz to 20 kHz: play pink noise and read the frequency response of the room
- Feedback finder: shows the most prominent frequency in hertz and the third-octave band to pull down on the equaliser
- Sweep from 20 Hz to 20 kHz in 12 seconds as a full-screen graph: the curve is drawn while the tone rises. Peaks and dips are marked and labelled, with zoom and landscape view
- Several measurements are kept side by side. Step through them, compare them one behind the other in a three-dimensional view, or average them into one curve
- With an audio interface: choose the input for the measurement microphone and the output pair (1/2, 3/4 …)
- EQ suggestion for a 31-band graphic equaliser from one measurement or the mean of several microphone positions: flat or a live curve, ±6, ±12 or ±15 dB, boosts limited
- Transfer function: the measurement microphone against the desk's signal on a second input, or against PA Check's own noise. Magnitude, phase and coherence on one screen, also while the band plays
- Delay and polarity of each speaker from the impulse response: keep the main system as the reference and read the value to set on a delay line for every other
- Reverberation time (T20) per octave from 125 Hz to 4 kHz, by interrupted noise
- Sound level in dB(A): LAF, LAF max, LAeq per minute and the loudest 30 minutes, as DIN 15905-5 counts them, calibrated with a 94 dB calibrator
- Calibration files of measurement microphones such as the UMIK-1 are applied to every curve
- A report as PDF and CSV for the organiser
Note: an iPhone microphone is not calibrated. Without a calibrator, levels are relative to the microphone's full scale; with one, the sound level is a guide, not a certified measurement. Nothing is recorded.
Privacy
The app collects no data. Everything you open or create stays on your device until you share it yourself.
Microphone: Used only while the analyser is switched on. The sound is analysed in memory; nothing is recorded, stored or sent.
- No account
- No ads
- No tracking
- Works without internet
Frequently asked questions
Are the levels calibrated?
No. A phone microphone is not a measurement microphone, and levels are relative to its full scale. The analyser is meant for the shape of the curve and for finding the frequency of feedback.
How loud should I start?
Quietly. Test signals can damage speakers and hearing. The app fades the signal in and limits the level to −12 dBFS. Turn the PA up slowly.
I bought the upgrade, but it is locked again.
Tap “Restore purchase” on the purchase card in the app. A one-time purchase is tied to your Apple account and does not have to be paid for again.
