Cerra Sound Lab
Cerra Sound Lab
Last recorded level
—dB
Approximate scale without calibration. Uncalibrated estimate: accuracy depends on the microphone and its processing.
Signal intensity (relative 0–100)
Sound over time · actual microphone signal · last 60 s · relative index 0–100
Guidance
Sin calibración no se emiten advertencias de riesgo: una señal digital relativa no permite establecer el nivel de exposición.
Cerra tip
Identifica la fachada y el horario con mayor exposición y prioriza esos espacios. Cualquier mejora de aislamiento requiere evaluación técnica y no se garantiza sin ensayos.
Values in dBFS: relative intensity of the microphone signal, not the environmental noise level.
Method: signal RMS for each frame, grouped into blocks of ~0,25 s. Leq: energy average (not arithmetic). L10: level exceeded for 10 % of the period. L90: exceeded for 90 % (background). Events: increases of 10 dB or more above L90; end when dropping below L90 + 5 dB.
Indicative measurement. A mobile phone does not replace a calibrated sound level meter or a professional acoustic study.
The tool uses your phone or computer microphone to record the sound signal in your space for a few seconds or minutes. It calculates an energy-average level, the minimum, the maximum, L10 and L90 levels, and individual noise events, such as a motorcycle passing by.
The browser provides the microphone's digital signal. This is used to calculate the level in dBFS (decibels relative to digital full scale) and an approximate estimate in dB. Data is processed on your device: the recording is neither transmitted nor stored.
Each microphone captures and processes sound differently. Many phones apply automatic volume control, echo cancellation or noise suppression, and very loud sounds can overload the microphone. This is why the estimated figure may vary between devices.
dBFS is a digital measurement: it indicates how close the signal is to the maximum the equipment can record and is always zero or negative. dB SPL is the actual sound pressure level in the environment, as measured by a sound level meter. Converting from one to the other requires calibration.
Calibration means comparing your device with an external sound level meter at the same place and time. Using that reference, the tool adjusts its scale and can display an indicative level in dB SPL or dB(A). A single-point calibration is not a certified measurement.
Use them for comparisons: the same space at different times, with the window open or closed, or two rooms in your home. Uncalibrated values cannot be used to draw health conclusions or verify compliance with WHO limits.
If you need a report for a complaint, a standard, an architectural project, or to size an acoustic solution, a calibrated sound level meter and a technical study are required. Cerra Sound Lab does not replace that measurement.