Sound Pressure Level Meter. This app uses the microphone to detect sound and convert it into an SPL value. FOR INDICATION ONLY. Results depend on your device and its hardware. The range between the noise floor and saturation may be only 20 dB on the worst devices, but could exceed 100 dB on the best devices. Features of this SPL meter include: Analogue Dial with Max and Min indicators. Weighting – A, C or None . (A weighting filters the high and low frequencies according to how the ear