It can sound if there is a speaker unit, why do you need a speaker?
1. In order to make the sound quality more beautiful, rich and pleasant.
2. The sound cannot be distorted after resonating through the speaker, and it has a high degree of fax performance. For example, a beautiful piece of music is composed of many musical instruments. The violin, oboe, clarinet, flute trumpet, bassoon, double bass, bass drum and percussion instruments cooperate with each other. If the bass pressure is a thousand times greater, the treble is only Twenty times bigger, only the low-frequency ensemble sound can be heard, but the violin sound cannot be heard. The sound size ratio of each frequency band of the music is deviated from the original, which is distortion.
The sounding principle of the horn:
1. How does the horn make a sound? The audio signal transmitted from the CD player, vinyl turntable and other sources is amplified by the amplifier, and the audio current passes through the voice coil of the speaker unit under the action of the magnetic field, causing the cone to vibrate and produce sound with the same frequency as the audio signal.
2. Why does the voice sound high and low? The level of sound is determined by the number of vibrations of the sound wave. The number of vibrations per second is expressed in Hertz (Hz), and the number of vibrations per second is a few hertz. The louder and lower the sound, the lower the Hz number. The higher and sharper the sound, the greater the Hz. The bass is about 80 or 90 Hz, and the soprano can reach 1100 Hz. The frequency range that the human ear can hear is 20 to 20000 Hz.
The speaker has three main functions
1. The role of the resonance box. Here the speaker unit is the sound source, and the sound waves it emits are resonated by the speaker products, so the sound is strengthened. This is like a violin. If there are only four strings and no gourd-shaped piano box, it is impossible to resonate, and it is impossible to produce such a loud, melodious, and pleasing sound. The same is true for the erhu, with a cylindrical resonance box covered in snakeskin. Similarly, the top and bottom of the big drum are cowhide, and the wooden barrel in the middle is the resonance box. Perhaps you also think that the thick and deep sound of the bass drum has a lot to do with its thick resonance box. You can try to take the speaker of the radio from its speaker to the outside, what will happen to the sound.
2. Solve the problem of sound short circuit. The sound effect of a speaker unit in free space is not ideal. Because at a certain moment, the cone moves forward, the air in front is compressed and the density increases, and the density of the air behind the cone must become smaller and sparse. Therefore, the front and rear sound waves are exactly opposite, and when the rear sound waves go around to the front, it will offset it, which is called a short circuit. This is especially true for low-frequency sound waves. Therefore, the bass effect of general speakers is particularly poor. If the speaker is placed in the speaker, the front baffle of the speaker separates the front and rear sound waves, or the two reverse sound waves are properly processed to provide a normal path for the sound emitted by the woofer and make the low-frequency sound waves more effective Radiate out to give full play to the performance of the bass unit. For example, the sound-absorbing material used absorbs the sound wave behind the cone to prevent its interference (this is the principle of a closed speaker). Or reverse the phase of the sound wave behind the cone to make it consistent with the front phase, and then send it to the front to add up to the front sound (this is the principle of an inverted speaker), so that it will not weaken, but will The sound is enhanced. In addition to most of the inverted speaker designs, there are also transmission line speakers that have evolved from the inverted type with more complex structure, more difficult production, expensive, better bass definition, wider dynamics and faster response.
3. Properly process the sound to reduce distortion and improve sound quality.