Acoustic angle:
Ultra-low frequency: below 125Hz
Low frequency: 125-25 Hz
Intermediate frequency: 25-5 Hz
Low intermediate frequency: 5-1 Hz
Intermediate frequency: 1-2 Hz < See the sound from 2Hz to 2Hz, while the high-frequency sound of the elderly is reduced to about 1Hz (or can be as low as 6Hz). People call sounds with frequencies higher than 2Hz ultrasonic waves, and those with frequencies lower than 2Hz infrasound waves.
after encountering obstacles, ultrasonic waves (higher than 2, Hz) and normal sound waves (2Hz-2, Hz) will propagate in the opposite direction to the original propagation direction, while some infrasound waves (lower than 2 Hz) can penetrate obstacles. Infrasound waves generated by Russian nuclear tests in the Arctic Ocean once circled the earth six times.
Infrasound waves with ultra-low frequency are more destructive to people than other sound waves (sound waves above 1Hz), and some of them can cause blood vessels to rupture and lead to death. However, the conditions for the generation of such sound waves are extremely harsh, and the chances of people encountering zd are very low.
Extended data:
Processing methods of different frequencies:
1, 3 ~ 8 Hz: This frequency band is the powerful frequency band of the floor drum heard outside. A slight increase can increase the shock, but not too much, too much will lead to chaos. At the same time, pay attention to the processing of human voice. This frequency band should be in the low-cut range.
2, 1 Hz: the main frequency point of bass, where lifting can increase the fullness and the feeling of the bottom drum hitting the chest. I like to raise the bass between 35 ~ 7 Hz and adjust the bottom drum at 1Hz and 25Hz, so that the two won't fight. The vocals in this frequency band should also be in the low-cut range.
3, 2 ~ 4 Hz: The upgrade of this frequency band also increases the wood texture of snare drum and the warmth of guitar. Attenuating this frequency band can make human voice, cymbals, etc. appear clear. 3-5 dB elevation at 4Hz can increase the warmth of human voice.
4, 5 ~ 8 Hz: It can be improved by about 3 ~ 5 dB, which can increase the strength of the music, make the bass show, make the drums warmer, and adjust the thickness of the guitar.