We must improve our ability to appreciate music. We must do more listening and more comparisons. Each type of instrument has its own unique spectrum and timbre. When playing a piece of music, the timbre emitted by the sound system differs from the timbre of the actual instrument performance in terms of how much it deviates. In order to perform listening comparisons, first of all, we should understand some concepts of acoustic nouns, auditory characteristics of the human ear, and main technical parameters of audio equipment.

I. Electroacoustic noun explanation

1. Pure tone: It has two meanings: (1) refers to a sound wave whose instantaneous sound pressure changes sinusoidally with time; (2) refers to a sound with a clear single tone.

2. Pitch: This refers to the lowest frequency component of a compound sound.

3. Overtone: The component of the composite sound that has a higher frequency than the fundamental tone. Its frequency can be an integral multiple of the fundamental frequency, or it can be not. Various musical instruments use different performance methods to produce harmonic components with different numbers and strengths, and even if the pitch is the same, they can have different timbres.

4. Acoustic wave: A mechanical wave that propagates in an elastic medium and originates from the vibration of the sounding body. Sound waves in the range of 20Hz-20KHz and frequencies higher than 20KHz are ultrasonic waves. Sound waves with frequencies lower than 20Hz are subsonic waves. Ultrasonic waves and infrasound waves generally do not cause hearing, and only the frequencies between the two waves can be heard. We can hear The sound waves arriving are called sound waves or audible sounds.

5. Sound field: refers to the area where sound waves exist in the medium. Different sound sources and environments can form different sound fields.

6. Loudness: Also known as "volume", the human ear feels a certain amount of volume. Depends on sound intensity, frequency and waveform.

7. Sound: Also called "timbre", it is mainly determined by the number of harmonics and the relative amplitude of each harmonic.

II. Auditory characteristics of the human ear

The ear's sensitivity to the sound's position, loudness, pitch, and timbre is different, and there are large differences.

1. A sense of orientation: The ability of the human ear to discriminate the sound propagation direction, distance, and positioning is very strong. This auditory characteristic of the human ear is called "a sense of orientation".

2. The sense of loudness: For small sounds, as long as the loudness increases slightly, the human ear can feel it, but when the loudness increases to a certain value, even if there is a large increase, the human ear feels no significant change. . Normally, the audible sound is divided into three parts according to the frequency multiplication relationship to determine the low, medium and high audio segments. That is, the bass frequency band is 20Hz-160Hz, the middle audio frequency band is 160Hz-2500Hz, and the high audio frequency band is 2500Hz-20KHz.

3. Tonal sensation: refers to a kind of special auditory comprehensive feeling that the human ear has to the timbre.

4. Focusing effect: The auditory characteristics of the human ear can be focused from a number of voices to a certain point. If we listen to the symphony, we concentrate our energy and hearing on the sound of the violin. The musical sounds of other musical instruments will be suppressed by the cerebral cortex, so that what you hear will be a pure violin. This ability to suppress varies from person to person. People who do regular hearing exercises have a strong ability to suppress it. We call this kind of auditory characteristics of the human ear a "focus effect." Doing more exercise in this area can improve the ability of human ears to distinguish the timbre, quality, resolving power, and level of a certain spectrum.

III. Main technical indicators affecting sound quality and timbre

1. Frequency range (unit: Hz): The working frequency band width of the power amplifier under the specified distortion and rated output power, that is, the range between the lowest operating frequency and the highest operating frequency of the power amplifier.

2. Frequency response (unit: decibel dB): The output gain of the power amplifier increases or decreases with the frequency of the input signal, and the phase lag changes with the frequency of the input signal. This indicator is the most important basis for assessing the quality of the power amplifier. The smaller the decibel value, the flatter the frequency response curve of the power amplifier, the smaller the distortion, and the stronger the signal's degree of reduction and reproduction. In addition to reproducing the rhythm of various musical instruments, a set of good audio equipment should reproduce the positions, distances, and scenes of various musical instruments.

Fourth, the meaning of high fidelity

No matter what kind of hue or model one prefers, if the timbre that is played out is auditoryly different from the timbre of the original instrument, it cannot be considered a good device. The real meaning of Hi-Fi is high reproduction. If your audio equipment can not restore the tone of the original instrument, then no high fidelity equipment. When we use subjective hearing to judge an audio device, we must pay full attention to this point, and do not influence the correct judgment and discriminative ability by personal preference.