AudioTool – SPL (deciBel) Meter with RT60, Leq, Spectrum Analyzer, Spectrogram, Chart Recorder, signal generator, polarity checker. There are two methods for calibrating the microphone.
Recommended by the magazine "Sound and Sight". Recommended by the magazine "Sound and Sight".
Features 1/1, 1/3 and 1/6 octave RTA modes, Leq (broadband, octave, variable duration), RT60 (wideband, octave), Spectrogram, peak frequency, fast, medium and slow filters, Flat & A / C Weighing and motion picture industry X Curve, Averaging, SPL chart recorder, Noise criterion, White / Pink Noise, Sinus, Square, Triangle, Swipe, Ramp and Pulse signals and speaker polarity check, L / R selection. RTA Store & Load, Hann windows , "Keep Screen On", pinch to zoom in, scroll to the center.
Exclusive ISO calibration 1/3 Octave – suitable for answering the microphone of your phone. Octave calibration discs move up or down to get a flat response and correspond to the total SPL with respect to the external counter. Save / restore Cal files (also supported by Dayton Audio iMM-6).
Use: home theater, audio-engineer, auto sound, etc.
AudioTool FFTs are sets of samples recorded on a microphone. Anti-aliasing is reduced using the Hann window. SPL is calculated in real time. Spectra can be stored as files on an SD card, then downloaded and displayed in real time. The Store button saves the current live spectrum. "Load" displays a list of stored spectra for selection.
To hide the buttons, touch the screen. To restore them, click again. To zoom in, click on the screen. To move the scale, drag it up or down (left or right).
The deciBel meter uses IIR filters and exponential averaging to calculate the weighted response of Flat, A and C at fast, medium and slow speeds.
A pair of cursors can be displayed on the RTA and Chart Recorder display: each can be moved to any position and displays SPL & time / frequency. Initially, both cursors are located in the middle of the screen – just drag them to a new position using the fingertip. Cursors can be turned on and off in the menu.
The speaker polarity control can be used to check if the loudspeaker is connected in phase: connect the AudioTool output to the speaker under test, select "Polarity" on the signal generator screen, then return to the RTA screen. If the speaker does not match the phase (polarity is canceled), AudioTool will display "Pol -", otherwise "Pol +++" if the speaker is in phase.
The Noise Criteria function (available from the menu) shows the set of NC loops superimposed on the 1/1 octave RTA display and the calculated NC NC real time value.
Chart Recorder shows the moving track of the SPL measurements in the last few minutes.
RT60 measurements can be performed by running the RT60 component with the "RT60" button, and then using a loud clap (or similar) to trigger the measurement. The RT60 can also be used with the Pink Noise from the AudioTool generator. RT60 times measures the amount of reverberation or echo in a room or hall.
The signal generator generates waves of white and pink noise, sinusoids, squares, triangles and waves, sinusoidal sweeps and pulses. The generator uses several cyclic buffers that are updated randomly to provide truly random white / pink noise. The Pink Noise algorithm uses the Kemmet method to tune White to Pink.
The accuracy of the frequency of generated periodic signals is usually about 1%. The superiority of a sine wave is good for most of the range of sound. In other and leading edges of other signals, audio signals are displayed and the artifacts of the frequency response in the upper bands are reduced, depending on which Android is used.
For a complete description of the AudioTool functions, refer to the online manual:
Please join a friendly AudioTool discussion group to request functions, find calibration files or report problems. Feedback is always welcome:
Disclaimer: The performance of AudioTool depends on your Android hardware and is not guaranteed to comply with any sound or security measurement standards.
v7.4 New recording / playback control for recording a microphone and playing audio.
AudioTool v7.4 APK / Mirror
AudioTool v7.3.1 APK / Mirror