How do you get -12 decibels?

Answer:
Decibel is a factor or a ratio and no unit.

If you have 1 volt and you damp it to 1/4 volt then you will get a damping of 12 dB.

Voltage daming = 20×log (1/4) = (-)12 dB.
First answer by Ebs2. Last edit by Ebs2. Contributor trust: 0 [recommend contributor recommended]. Question popularity: 1 [recommend question].