How Is DB Gain Calculated? Gain is defined as the ratio of the output power to the input power in dB. Assume that the input power is 10 mW (+10 dBm) and the output power is 1 W (1000 mW, +30 dBm). The ratio will be 1000/10 = 100, and the gain will be 10
How Do You Calculate 3dB Cutoff Frequency? The cutoff frequency of a device (microphone, amplifier, loudspeaker) is the frequency at which the output voltage level is decreased to a value of (−)3 dB below the input voltage level (0 dB). (−)3 dB corresponds to a factor of √1⁄2 = 1/√2 = 0.7071, which is 70.71%