DB SPL with Grove sensor

Hi,

I'm a new to arduino sensor and I have a grove loudness sensor. I want to convert value from AnalogRead to DB

float volt_cal = sensorValue * (5.0 / 1023.0); is the value in volt.
20 * Log10 (Vout / Vin) = dB SPL.

If I take: Vout=volt_cal and Vin=1V is this correct?

Below is the datasheet of the sensor:
wiki.seeed.cc/Grove-Loudness_Sensor/

Thanks in advance for your help.

What is the 0db level ? Say you read 10 mV when silence prevails, then 4000 mV (4V) with noise,
4000 / 10 = 400, 20 * log 400 = 52.04 db.

Hi 756E6C,

Thanks for your answer.
If I understand I have to measure the level when silence prevails. Can I have this from sensitivity?

Best regards.