Blue Whale Vocalization

real time - sound frequency about 16 Hz
2x faster - sound frequency about 32 Hz
4x faster - sound frequency about 64 Hz

The source level of sounds made by blue whales is between 155 and 188 decibels. All blue whale groups make calls at a fundamental frequency of between 10 and 40 Hz; the lowest frequency sound a human can typically perceive is 20 Hz. Blue whale calls last between ten and thirty seconds.