Some little knowledge about HIFI hearing

                                Some little knowledge about HIFI hearing

dynamic

Dynamic is the range covered by the smallest sound and the loudest sound. The equipment must have sufficient margin, the output power must be large, and the size of the speaker must be large, which is also related to the gain of the equipment, so dynamics cost a lot of money. However, there is often a contradiction between dynamics and sound quality. The output power of the amplifier must be large, and the power vacuum tubes or transistors used must be more, and the speaker units must be more. But multi-power vacuum tubes and transistors, and multi-speaker units will definitely affect the sound quality.

sense of pressure

Some people like to use the D turntable to directly push the post-amplifier, or use the pre-amplifier without gain (passive pre-amplifier), because the gain is not enough, so they can’t get enough gain; or the output power of the amplifier is too small, the power capacity The margin is not enough, and a greater sense of force cannot be obtained. Even if an amplifier with high output power and high capacity margin is used, it will be useless if the speaker system is not large enough and the efficiency is not high enough to emit enough energy.

Vocal order (high and low frequency percussion)

All kinds of instruments, whether blowing, pulling or singing, have their "sounding sequence", but percussion instruments are easier to distinguish the process of the sequence of sounding. In general percussion, cymbals, pianos, triangles, etc. are high-frequency instruments, while bells, drums, etc. are low-frequency instruments, which rely on the "sounding process and sequence" of percussion. For example, the "dong" sound of drumming, if you analyze the "dong" sound carefully, you should be able to hear the moment when the drumstick hits the drum skin, and then the sound from that point extends from the inside to the outside to the entire drum surface. , and then transmit the vibration of the drumhead to the resonance box of the entire drum, and then transmit it radially to every corner of the entire concert hall from a point on the stage.

If the vocal sequence is obvious, you can hear every process of the vocalization. If the vocal sequence is not obvious, you may only hear the sound or the sound, and you may also hear the sound, but there is no ending rhyme. The same goes for high-frequency instruments, such as the "ding" sound of a triangle, and every process should also be heard.

The order of sound production is related to the correctness of the time phase of the audio equipment (it is also related to the placement of the speakers). Because some audio equipment performs well in high-frequency percussion but not in low-frequency percussion, or the performance of low-frequency percussion Good but high-frequency percussion is not good, so we divide the sounding sequence into two items with different high-frequency and low-frequency percussion.

Sense of speed

The amplitude of the sound produced by various musical instruments is long or short, fast or slow. Instruments with higher frequencies have smaller amplitudes and faster speeds; instruments with lower frequencies have larger amplitudes and slower speeds. Therefore, the speed varies with different musical instruments, and it is not blindly pursuing the faster the better.

For equipment with a particularly fast sense of speed, when playing back low-frequency instruments, the sound ends too quickly and there is no aftertaste, which is incorrect. But if the sound of the audio equipment is too slow, it is not right, so whether the speed presented by the audio equipment is consistent with the original speed of all musical instruments is one of the basis for us to judge the audio equipment.

linear power

The frequency response of some equipment is not bad when the volume is low, but when the volume is high, the high frequency and low frequency cannot be amplified synchronously, resulting in a prominent mid-frequency phenomenon, the sound field also rushes forward, the layers are also messed up, and the sound is rough This is the phenomenon of power nonlinearity. This phenomenon often occurs when the capacity of the power transformer is not large enough, the output power margin is not enough, the chassis structure is not stable enough, the power cord is not thick enough, or the carrying power of the speaker unit is not high enough, the speaker is not strong enough, etc.