Sound Meter (SPL - sound pressure level) is an app which can measure the actual sound level meter with decibels (dB). Sound meter is also known as sound level meter, decibel meter (dB meter), noise meter, sound pressure level meter (spl meter). It uses your built-in microphone and shows a reference. We had calibrated many devices with the actual sound level meter with dB. You have to know that the built-in microphones were aligned to human voice (300-3400Hz, 40-60dB). Therefore the maximum values are limited by the hardware limitation, and very loud sound (100+ db) cannot be recognized. Remember that it's only a device for fun and please use it as an auxiliary tool. Levels of Noise In decibels (dB): 140 dB - gun shots, fireworks 130 dB - jackhammers, ambulance 120 dB - jet planes taking off 110 dB - concerts, car horns 100 dB - snowmobiles 90 dB - power tools 80 dB - Alarm clocks 70 dB - traffic, vacuums 60 dB - normal conversation 50 dB - moderate rainfall 40 dB - quiet library 30 dB - whisper 20 dB - leaves rusting 10 dB – breathing If you have any problems, contact with us: [email protected]