DiGi+ SPL Audio Analyzer

This application brings the functionalities of a Sound Level Meter (SLM) and a basic Real Time Spectrum Analyzer (RTA) to your phone.

Analyze the ambient (background) noise and the traffic noise (TNI)!


>>SLM Main features:
• 3 measuring modes (Dynamic, Average, Cumulative)
+ 1 weighting filter curves: dBA according to DIN-IEC 651
• simple calibration settings
• sound level versus time chart
• current dB value, avg (Leq), min and max display
• audio threshold trigger
+ sound level distribution chart
+ accumulated sound level chart
+ current value, L90, L50 and L10 values display
+ TNI (Traffic Noise index) display
+ exporting of measures, chart data (CSV) and screenshot (PNG)
• tested with samsung galaxy S S2 S3 S4
• sharing of text values and screen bmp


>>RTA main features:
+ sound level versus linear frequency chart
+ 1/3 octave chart
+ Dynaminc and AVG smoothing mode
+ spectrum zoom and swipe
+ fixed FFT size ( 2048, about 20 Hz accuracy )
+ 4 values versus selected frequency component displayed (current, mean, max, min)
+ 20hz/22kHz band, 44100 Hz sampling rate


>>Data collection
The application relies on the mobile microphone signal. To achieve the best results consider the following:
1) Easy Calibration (only the first time): Some mobiles are automatically calibrated in the first installation phase. For details see the calibration section of the user manual.
2) keep your fingers away from the mobile microphone
3) silence your phone to avoid any ring tones, vibrations and other sounds
4) orient the phone microphone toward the noise source keeping the correct distance
5) click on the function buttons


>>Troubleshooting
1) Wrong SPL calibration: See the Calibration section and type the right calibration values
2) No signals detected below 20dB or over 100dB: most smart phone microphones do not work under 20 dB or over 100 dB
3) Signal attenuation near band limits: the mobile mic may attenuate frequencies <100 Hz and >15000 Hz

Read the embedded User Guide: for any info or troubleshooting you can contact us at [email protected].