NoiSee Sound Level Meter

Professional-grade SLM

Measuring sound is what we do. NoiSee - Worthy of the name "Sound Level Meter"

NoiSee is an intuitive professional-grade sound level meter for Android. It features all the tools that are expected from a professional ANSI or IEC compliant Sound Level Meter. All filters, averaging modes and statistics meet or exceed class 2 requirements of relevant ANSI and IEC standards. NoiSee is specifically designed to meet the requirements for Occupational health and live sound measurements. The application was created by the team that has over 20 years experience in calibration, owning a Sound Level Meter calibration laboratory meeting the ISO 17025 requirements. The same calibration equipment was used for the development of this app.

IMPORTANT NOTE
Supported phones, that have internal microphone calibrated and compensated Frequency response for better Frequency linearity:
- Galaxy S10e
- Galaxy S22
- Galaxy S23
- Galaxy S23 Ultra
- Galaxy A52
- Galaxy A54
- Pixel 3 XL
- Xiaomi 12 Pro
- Nothing CMF Phone 2 Pro

For other devices we make an estimation of the internal microphone Sensitivity, but it can be more than 10 dB off.

The App also includes parameters and UI optimizations for analysis of live events and live audio monitoring including the running LAeq (5min, 10min, 15min and 20min averaging interval) and an overlaid standard live sound target curve in spectrum analysis.

The initial calibration works incredibly well and has been verified for the differences in microphones between different devices of the same model. It is determined with testing in an anechoic chamber meant for calibration of professional Sound Level Meters. We do not recommend changing the initial calibration for supported phones since we have established that the internal sensitivity of the microphones has insignificant variation between different devices.

The app makes full use of your device's dynamic range which is approximately 35 dB to 95 dB (re. 20 uPa) and frequency response range which is from 40 Hz to 18 kHz and 35 dB to 110 dB for frequency range from 100 Hz to 8 KHz.

SOUND LEVEL METER
History view (also called profile view) of all relevant parameters.

Parameters offers a view of all the Statistics of the current measurement (Percentiles from the ISO 1996) which are also visualized as a histogram.

- All relevant time weightings available: Fast, Slow, Impulse, and Equivalent
- All relevant sound measurement parameters are measured: Leq, LCpeak, LAFmin, LASmax, ...

Spectrum view offers a view of time-history of the sound Level which is frequency and time-weighted.

Special care has been taken to design the CPB (Constant percentage bandwidth) frequency analysis according to the IEC 61260 and ANSI S1.11 for octave analysis with options for 1/1 and up to 1/24 octave display.

NOISE AT WORK
Occupational Health compliant (ISO 9612, OSHA/NIOSH) and parameters including: Noise DOSE, Elapsed time. Parameters such as Threshold, Reference level and Exchange rate can also be set to custom values.

Special parameters: LEX 8h, Projected DOSE, Time to reach 100% DOSE (in hh:mm:ss).

EXTERNAL MICROPHONES
NoiSee has been tested with external microphones MicW i436 and MicW D236, which are calibrated measurement microphones complying with the Class 2 (IEC 61672) sound level meter standard. If you use an acoustic calibrator, NoiSee can perform automatic calibration.

We took special care to develop and implement robust native drivers for dongles that can be used when connecting i436 to a USB-C based device. This unlocks the ability to measure all the way up to 130 dB. Our driver is very generic and should work with any dongle/adapter.

IN-APP PURCHASES
Premium octave analysis:
- Non-standard time weightings (1/16th of a second up to 16 seconds)
- Spectrum analysis in ⅓ octave or less
Logging:
- One second logging of spectrum and total parameters
- Profile view beyond 2 minutes
- Ability to export in CSV
Recording:
- 24-bit WAV or AAC