Everyone will say: the high pitched sound of this pair of speakers is too strong, and the low pitched sound is too low. This is the quantitative dispersion in the high, medium, and low frequency bands. The problem arises from the confusion of not being accurate enough if the bandwidth from 20Hz to 20KHz is only divided into three segments. What exactly is your low voice referring to? How low is it? In order to make the described text more accurate, it is necessary to subdivide the bandwidth from 20Hz to 20kHz.

According to the classification method of TAS and Stereophile in the United States, it is very simple. They subdivide each segment of high, medium, and low into three smaller segments, which becomes the "lower intermediate frequency, intermediate frequency, and higher intermediate frequency" classification method. This classification method is like the law of twelve averages, quite regular. However, when used on Chinese people, some translation issues arise, such as whether we refer to "lower mid frequency" as "mid low frequency" or "low mid frequency"? So what about higher low frequencies? Is it high and low frequency? For Chinese people, this classification of foreigners may not work. Therefore, a long time ago, I referred to the bandwidth of the instrument and the orchestra's title of motion and stillness, and divided the frequency of 20Hz-20KHz into seven segments: extremely low frequency, low frequency, medium low frequency, medium frequency, medium high frequency, high frequency, and extremely high frequency. The nouns in these seven paragraphs are in line with the customary titles of ordinary Chinese people, and are easy to remember without confusion.

Extremely low frequency

I call the octave from 20Hz-40Hz extremely low frequency. There are very few instruments in this frequency range, and only instruments such as the low violin, low bassoon, tuba, organ, piano, etc. are needed to reach such a low range. Due to the fact that this extremely low frequency is not within the range of the instrument, composers rarely write notes that low. Unless pop music is deliberately organized using electronic synthesizers, extremely low frequencies have little real use for audio enthusiasts. Some people mistakenly believe in an assignment, saying that although the fundamental note of an instrument is not that low, overtones can be as low as the fundamental note. Originally, this was incorrect, as the fundamental note of the instrument is the same note, and the note will only be twice, three times, four times, or five times? Wait to climb higher without any downward sound. This is like when you tighten a string, and the full length vibration frequency of the string is the fundamental, half, one-third, quarter, fifth? A vibration of equal chord length is called overtone. The sum of fundamental and overtones is the timbre of an instrument. In other words, even if the pitch (pitch) of a violin and flute is the same, their timbre will have different manifestations.

Low frequency

The frequency range from 40Hz to 80Hz is called low frequency. What instruments are there in this frequency band? Big drum, low pitched violin, cello, low pitched bassoon, bassoon, low pitched elastic horn, low pitched clarinet, tuba, French horn, etc. This frequency band is the great contributor to the solid low-frequency foundation. Generally, most people mistake this frequency band for extremely low frequency because it sounds very low now. If there is too little sense of quantity in this frequency band, there will definitely be no abundant and surging sensation; And it will lead to prominent mid to high frequencies, causing a loss of balance between motion and stillness, making it less durable to listen to.

Mid low frequency

Between 80Hz and 160Hz, I refer to it as mid low frequency. This frequency band is the most headache inducing segment for Taiwanese audio enthusiasts, as it is the culprit behind the deafening sound. Why is this frequency band particularly brief with peaks? This is related to the length, width, and height scale of the small room. Most people try their best to absorb this frequency band in order to eliminate this annoying peak, so that their ears do not become loud. Unfortunately, when your ears don't sound loud, both the lower and upper mid frequencies may have become sunken due to the absorption of the mid to low frequencies, resulting in a slimming effect and a lack of fullness. Unfortunately, most people only believe that this phenomenon is correct because the peak disappears. This is one of the reasons why there is not enough activity in many households. The instruments in this frequency band include those mentioned in the low frequency band earlier. By the way, the timpani and male low voice should also be added.

intermediate frequency

The frequency spanning between three octaves (320Hz, 640Hz, 1280Hz) from 160Hz to 1280Hz is called the intermediate frequency. This frequency band almost includes all instruments and vocals, so it's the right frequency band. Readers' misunderstandings about the range of musical instruments also occur here. For example, most of the range of a violin is in this frequency range, but most people mistakenly believe it is very high; Don't think that a soprano has a high range, generally speaking, her range is only at the upper limit of the mid range.

From the above description, you must also understand how important this mid frequency is in terms of sound. As long as this frequency is depressed, the manifestation of movement and stillness will immediately become thinner. Sometimes, this thinness is simply explained as "false condensation". I believe many audio enthusiasts are unaware of the mid frequency dip. The importance of this frequency band can also be analyzed from the crossover point of the two tone horn. The frequency division point of a typical two tone speaker is mostly around 2500Hz or 3000Hz, which means that high pitched units are responsible for frequencies above 2500Hz, and medium to low pitched units are responsible for frequencies below 2500Hz. This 2500Hz is about twice the frequency of 1280Hz, which means that in order to avoid too much distortion of the crossover point at the mid frequency, planners have raised the crossover point to twice the upper limit of the mid frequency. In this way, the maximum mid frequency can be declared by the mid low sound unit. If this statement is correct, what is the use of treble monomers? If you have ever placed your ears close to a treble unit and heard a hissing sound, that is where most overtones are located. If there is no high pitched unit announcing a hissing sound, singing music with only a mid low pitched unit will inevitably be extremely dull. Of course, if it is a three tone speaker, the vast majority of this mid range will be included in the mid range unit.

Medium to high frequency

The frequency range from 1280Hz to 2560Hz is called medium to high frequency. What instruments are there in this frequency band? The violin has about a quarter of its higher range, including the upper limit of the viola, the high range of the flute, clarinet, oboe, half of the lower range of the piccolo, cymbals, triangle iron, etc. Please note that the speaker is not in this frequency range. Originally, the medium and high frequencies were easily recognizable, with only the high range of the string ensemble and the woodwind being the medium and high frequencies. Many people may mistake this frequency band for high frequency, so please be extra careful.

high frequency

I refer to the frequency range from 2560Hz to 5120Hz as high frequency. This frequency domain is now rarely involved in instrument performance. Due to the fact that most instruments, except for the upper range of the violin, piano, and piccolo, do not appear in this frequency range. From the frequency division point of the speaker, we can observe that this frequency domain is entirely presented in the treble unit. As I mentioned earlier, when you approach the treble unit with your ears, what you hear is not the movement of the instrument, but a hissing sound. From the manifestation of treble monomers, it can be once again proven that treble monomers rarely declare the fundamental of instruments or vocals, they only declare the high overtones of the fundamental.

Extreme high frequency

I call it extremely high frequency in the frequency range of 5120Hz-2000Hz. You can understand from the reality that high-frequency instruments are rarely presented, that extremely high frequencies contain all the overtones of instruments and vocals. Generally, the overtones of musical instruments tend to have lower energy at higher altitudes. In other words, the treble unit needs to be made very sharp and can be understood as a very delicate sound. From here, a task that troubles the production of individual speakers arises, which is how to achieve the best of both worlds? What is "two complete"? Have you ever thought that if a tweeter unit plans to push the diaphragm with a very small current in order to understand all the fine overtones, then the high-energy high-frequency and intermediate frequencies also served by this tweeter unit are likely to frequently be in a distorted state, as the energy in these two frequency bands is much greater than that in extreme high-frequency. This was also one of the reasons why many speakers on the market at that time understood extremely high frequencies very well, but they were simply too sharp.

Article source: LED Bluetooth audio system http://www.zbchip.com/