One: the distribution of volume sense of each frequency band and its control ability
The sound is finally played back through a certain physical effect, and the sound is generally divided into certain frequency bands such as treble, midrange and bass according to the definition of physical acoustics.
Many acoustic experts and sound experts have come up with the bandwidth of the reference musical instrument and the name of the sound by the orchestra. The 20Hz-20KHz frequency is divided into "ultra low frequency (super bass), low frequency (bass), and mid-low frequency (mid-bass). ), mid-frequency (mid-range), mid-high-frequency (mid-treble), high-frequency (treble), and ultra-high-frequency (super-treble).
The definition of such seven frequency bands is easier to understand and remember than the simple definition of high, middle and low frequency bands. The following explains one by one:
Ultra low frequency (subwoofer)
The low (frequency) range refers to the frequency of the sound or the fundamental frequency of the instrument below 100 Hz.
According to the division method of seven frequency bands, we call the octave from 20Hz-40Hz as ultra-low frequency (subwoofer).
When replaying the frequency of this frequency band, it is necessary to rely on the resonance of the physical environment itself, and at the same time, the sound of this frequency band has lost its obvious location positioning. The ultra-low frequency (subwoofer) part can extend all the way down to frequencies below 10 Hz (infrasound).
In fact, when the frequency is lower than 20Hz, the hearing ability of human ears is already very poor, but you can still feel their presence through the conduction of the chest cavity and bones. This is what people often say that the super bass has a beating. The feeling in the chest! The strong subwoofer can also make people feel vomiting because the subwoofer acts on the character of the human body.
There are very few instruments in this ultra-low frequency (subwoofer) frequency band, probably only instruments such as double bass, bass bassoon, tuba, pipe organ, and piano can reach such a low range.
Since this extremely low frequency is not the most beautiful range of an instrument, composers rarely write the notes so low, and some popular music uses electronic synthesizers to deliberately arrange it. Therefore, ultra-low frequency is not too practical for pure audio fans. Unless you are a big dynamic movie music fan, you often need super bass!
For the low frequency (bass) area, especially the recording and replay of the ultra-low frequency (subwoofer), two things should be paid attention to: one is that the low-frequency area must have enough low-frequency lower limit and enough low-frequency components; the other is, The equipment's ability to control low frequency.
With the continuous development and advancement of current technology and the development of recording technology to the current digital age, the response to ultra-low frequency can be easily achieved below 10Hz, but the replay of audio equipment is often lacking!
Having said that, is this part of the ultra-low frequency (subwoofer) sound that can be perceived but difficult to hear normally, is it meaningless?
no! Because practice has proved that in actual music performances, some well-designed music environments have enough ultra-low frequency (subwoofer) components when performing interpretations.
When recording and replaying, if the sound components of this part can be properly restored, the low frequency during replay will be more relaxed, and the replayed sound field will be wider and far-reaching!
Therefore, some good audio equipment can replay the ultra-low frequency (subwoofer) part very well, which makes people feel particularly comfortable, while the lack of ability will make people feel that the volume is insufficient and the bass is dry and thin.
In addition, since the resonance time between the ultra-low frequency (subwoofer) and the environment is relatively long, and the frequency of this frequency band itself is in piston vibration, it is easy to produce inertia (delay) during replay, and this additional inertia ( Delay) will cause the turbidity of the replay, and the sound reproduction is not clear enough. Once the equipment's low-frequency control ability is not enough, it will produce such a turbid feeling, which is very unpleasant!
Therefore, for audio enthusiasts, the ability to control the ultra-low frequency is also not to be ignored. Simply put, your audio system is more capable of controlling the ultra-low frequency (subwoofer) part. A more vivid expression is the brake of the speaker. ability! A good sound system can not only produce sounds of this frequency when there are ultra-low frequency signals, but more importantly, waiters without these signals should stop vibrating immediately! Are you saying it is difficult!