Busy car dragons, troubled cities, low-headed people, in the city forest, late at night, for those who are used to loneliness, after work, in addition to hope that there will be a late-night canteen to fill a few small dishes In addition, I hope that on the way home, there are so many good songs to accompany my peers. The earphone is a personal sound, and it has a wide range of uses, and you can enjoy your own world in a specific environment. How much do you know about headphones?
—— Headphones classification——
1, simple division, can be divided into head-mounted and earbud-type head-mounted: generally larger, has a certain weight, so it is not convenient to carry, but its performance is very strong, can be isolated from the world to enjoy the music .
Earbuds: It is easy to go out and listen to music because it is small. These headphones are mainly used in mobile phones, CDs, MP3 players, and MDs.
2, according to the principle of transduction, can be divided into dynamic and static two categories, although in addition to these two categories are still magnetic, electret, etc., but have been eliminated or used in professional markets There is very little possession and we will not discuss it here.
Dynamic headphones (electric): Most of the earphone earphones are of this type. The principle is similar to ordinary speakers. The coil in the permanent magnetic field is connected to the diaphragm, and the coil drives the diaphragm to sound under the signal current. Dynamic headphones are more efficient, and most of them can be used for audio output on headphones.
Electrostatic earphone (capacitive): The diaphragm is in a changing electric field. The diaphragm is extremely thin and accurate to a few micrometers (currently STAX's new generation of electrostatic earphone diaphragm has been accurate to 1.35 microns), and the coil is driven by electric field force. The diaphragm sounds. The sound pressure level that can be reached by an electrostatic earphone is not as large as that of a dynamic earphone, but its response speed is fast, and it can reproduce various minute details with extremely low distortion. Due to its precise structure, high material requirements, and mostly manual assembly and debugging, it is expensive.
In addition, there is a dual-frequency headphone: the two-way headphone is a two-stage crossover headphone that combines the advantages of both electric and capacitive on the basis of a semi-open headphone. It combines the advantages of four types of electric, capacitive, closed, and open headphones. These headphones are outstanding in terms of dynamic range, transient response, playback quality, tone thickness, etc., and it Accurate sound analysis is the best choice for music enthusiasts.
From the use situation: Generally speaking, the electric earphone has the characteristics of simple structure, stable sound quality and low price. It is suitable for general people to choose, it can meet the general needs; capacitive earphones, good sound quality and frequency bandwidth, but Due to the complexity of the process, the price is relatively high, suitable for enthusiasts to choose, its listening quality is quite good.
3, according to the degree of openness is mainly open, semi-open closed (closed): it is wrapped by your own soft sound pad to make it completely covered. Because these headphones have large sound pads, they are also large in size, but with the sound pad, they can be used in noisy environments without being affected. The earmuffs have a large pressure on the ear to prevent the sound from entering and exiting, and the sound is correctly positioned. This is common in the professional monitoring field, but one of the disadvantages of this type of earphone is that the bass sound is severely dyed, and the W100 is an obvious example.
Open: It is a popular headset style. This type of machine is characterized by making a sound-permeable ear pad by using a sponge-like microcellular foamed plastic. It is small in size, comfortable to wear, no longer uses a heavy dye pad, so there is no sense of isolation from the outside world, the sound can leak, and vice versa can also hear the outside world. If the headset is open to a high degree, you can hear the sound from the other side of the unit, forming a certain mutual feedback, making the sense of hearing natural. But its low frequency loss is large, and some people say that its low frequency is accurate. Open-type headphones generally have a natural sense of hearing and are comfortable to wear. They are commonly found in home hifi/target=_blank>HIFI headphones.
Semi-open: A new type of earphone that combines the advantages of both closed and open headphones (it is a hybrid, combining the advantages of the first two headphones and improving the deficiencies). This type of headphones uses a multi-diaphragm structure. In addition to an active active diaphragm, there are a number of passive driven diaphragms. It has a lot of low-frequency descriptions, high-frequency descriptions, bright and natural, clear layers, and many other features that are widely used in many higher-end headphones today.
4, according to the main use of household, portable, monitoring, mixing, head recording, etc.
—— Headphone parameters and sound quality terms –
1, headset related parameters
Impedance: Pay attention to the difference between the meaning of resistance. In the world of direct current (DC), the effect of an object on current obstruction is called resistance, but in the field of alternating current (AC), in addition to resistance blocking current, capacitance and inductance can also hinder. The flow of current, this effect is called reactance, and our daily impedance is the sum of the resistance and the reactance in the vector.
Sensitivity: The sound pressure level that can be emitted by the earphone when the input power of 1 mW is input to the earphone (the unit of sound pressure is decibel, the louder the sound pressure is, the louder the volume is), so the higher the sensitivity and the smaller the impedance, the easier the earphone is. Sound, the easier it is to drive.
Frequency response: The sensitivity value corresponding to the frequency is the frequency response. The image is the frequency response curve. The range that human hearing can reach is about 20Hz-20000Hz. The mature earphone technology has reached this requirement.
2, sound quality evaluation terminology
Speech field: The range between the highest and lowest sounds that an instrument or vocal can achieve. Tone: Also known as a sound, one of the basic attributes of sound, such as erhu and pipa, is a different tone.
Sound Dye: The opposite of the natural neutrality of music, that is, the sound is dyed with some features that the program itself does not have. For example, the sound that is heard in a jar is a typical sound. The sound dye indicates that some of the components are added (or reduced) in the reproduced signal, which is obviously a distortion.
Distortion: The output of the device cannot fully reproduce its input, resulting in distortion of the waveform or an increase or decrease in signal components.
Dynamic: Allows you to record the ratio of the largest message to the smallest message.
Transient response: The ability of the equipment to follow burst signals in music. The equipment with good transient response should respond immediately when the signal comes, and the signal will stop when it stops, and it will never drag the water. (Typical instrument: piano)
Signal-to-noise ratio: Also known as the signal-to-noise ratio, the useful components of the signal are compared to the strength of the noise, often expressed in decibels. The higher the signal-to-noise ratio of the device, the less noise it produces.
Air Sense: An acoustic term used to indicate the treble or the spatial separation between instruments in the sound field. At this time, the high frequency response can be extended to 15 kHz to 20 kHz. The antonyms are "dull" and "thick". Very abstract words, not a sense of space. It is more suitable for listening to large works or programs that are played on larger venues. It is a high frequency and scattered sound.
Low frequency extension: refers to the lowest frequency that audio equipment can reproduce. It is used to determine the extent to which the sound system or speaker can dive when replaying the bass. For example, a small subwoofer can have a low frequency extension of 40 Hz, while a large subwoofer dive to 16 Hz.
Bright: refers to highlighting the high frequency range of 4kHz-8kHz, where the harmonics are relatively stronger than the fundamental. There is nothing wrong with the brightness itself. The live concerts have bright sounds, but they are bright enough to be well-balanced, too bright (or even whistling) to be annoying.
Sound quality: The term sound quality is not abstract. When you turn on a radio to listen to music or news, when you feel it sounds, the radio broadcasts the announcer's voice sweet and layered. The distortion is small, the treble is bright when the music is broadcast, the bass is rich, and the reverberation is good. You naturally can't help but marvel: "This radio sounds good!" Sound quality is the most basic and broadest evaluation term for evaluating audio equipment.
Tone: Sound will be colored like light, but it is not seen with the eyes, but with the ears. The warmer the sound, the softer the sound, and the harder the sound, the harder it is. The tone can be described by the eyes of “beauty†and “nobleâ€. For example, when listening to the violin, you can say that the sound of the violin is really cold or really warm.
Sound field sense: This includes the shape of the sound field, front and rear position, height, width, depth, etc. These items can be expressed in a concrete way, that is, the sense of presence of the sound field. This is the feeling that the listener and the speaker position, the space relationship between the three to achieve a more subtle, appropriate fusion point.
Layering: This is the clarity of the vocalization of the instrument in the sound field, and the clarity of the interval between the instrument and the instrument. This process feels like a piece of wood cross-section of the annual ring of wood.
Positioning: In simple terms, the vocal or instrument sounds are clearly visible and the position is accurate. Generally speaking, the sound is floating, that is, the specified position is not good. In the sound field, the positioning of the instruments on both sides is usually better, and the sense of positioning of the instrument in the center of the sound field is relatively poor. This is one of the reasons why the middle channel is added to the surround sound effect. Adding the middle channel helps the positioning.
Transparency: The best sense of transparency, the sound is not harsh and the most tolerant, each pair of human ears is not the same as the tolerance of hearing and intolerance. Therefore, there are different standards for the quality of transparency.
Image and body sensation: As the name implies, strong image power is the ability to condense the illusory audio image into a solid body. It is also the ability to express the sound or the sound of a musical instrument. A good-quality audio equipment will make the audio image more embossed and more three-dimensional.
Analytical power: The subtle changes can be expressed clearly. There are both analytical power at low level and resolution at high level. The resolution of low level and high level is what we call resolution.
Overall balance: mainly refers to the appropriate amount distribution of high, medium and low frequency bands. Reasonable high, medium and low volume sense is the overall balance. Listening to music feels that the music is soft but powerful, bright, cheerful and layered, clear, harmonious and three-dimensional. The sense of presence is strong, so the overall sound equipment is reflected in the whole.
Pine scent: Generally used for the evaluation of string music, the common sayings are "sweet scent", "sweet scent" and so on. In fact, this is a sound with a higher pitch (higher frequency), lower loudness, and a burr but sounds pleasant.
Elasticity: Commonly used for the evaluation of low frequencies, more abstract, with strength, fullness and pleasantness.
Cold and warm: Both are pleasant, the cold sound is clear, strong, and even slightly burr, the warm sound is bright, round, and the intensity is not so abundant.
Plump and cognac: The fullness of the voice is full, broad, harmonious, pleasant and has a certain loudness, while the dry voice is thin, divided, dry, uncomfortable and generally louder.
Width and Narrow: Both are directly related to the frequency range of the playback program. If the replay program high music and bass instruments are very good, giving a broad feeling, it is called wide. On the contrary, when playing a program, the high-music and bass instruments are basically inaudible. Only the intermediate frequency, just like the sound heard on the phone, is uncomfortable. This is narrow.
Loose and tight: If a sound is scattered, relatively round, has a certain amount of moisture and is not uncomfortable, it is called loose, and the sound is strong, but it is dry and dark, which is not pleasant.
Fat and thin: The fat finger is too full, meaning that the low frequency is too much and the water is quite a lot, that is, there is a certain frequency distortion (the low frequency is excessive) and the reverberation is heavy. The concept of thinness is comparable to cognac.
—— Amplifiers -
Amplifiers are a general term for power and preamplifiers. They are generally classified into transistors (stone machines) and electron tubes (tubes).
Power amplifier: referred to as power amplifier, an electronic device used to enhance the signal power to drive the sound of the speaker. A power amplifier without an accessory function such as source selection and volume control is called a post stage.
Preamplifier: The preamplifier and control section before the amplifier, used to enhance the voltage amplitude of the signal, providing input signal selection, tone adjustment and volume control. The preamplifier is also called the preamplifier.
Class A amplification (class-A)
Also known as Class A amplification. A working state for the amplifier. At this point the transistor or tube amplifier will amplify the entire audio signal.
Class B amplification (class-B)
Also known as Class B amplification. A working state for the amplifier. At this point one transistor or tube amplifier will amplify the positive half of the audio signal, while the other transistor or tube amplifier amplifies the negative half of the signal.
Class A and Class A (class-AB)
Also known as class AB amplification. A working state of the amplifier. At this time, the output stage of the amplifier is in the Class A amplification state when the output power is low, and is converted to the Class B amplification when the output power is high.
—— Headphone wire——
Most of the headphone cables are made of copper. The general purity (usually expressed by a few N, such as 4N, 6N...) is higher the conductivity, and the smaller the signal distortion, the following four types are common.
TPC (electrolytic copper): purity is 99.5%
OFC (Oxygen Free Copper): 99.995% purity
LC-OFC (linear crystal oxygen-free copper or crystalline oxygen-free copper): purity above 99.995% OCC (single crystal oxygen-free copper): the highest purity, above 99.996%, divided into PC-OCC and UP-OCC
—— Front-end equipment——
Many hifi/target=_blank>HIFI enthusiasts are used to separating the phonograph into two parts, the turntable and the decoder, to get better sound quality music.
Front-end: A signal source in a multi-finger audio system, such as an LP compact jogger or CD player, sometimes referred to as a preamp in a tuner (receiver) that processes signals received from the radio.
CD turntable: A machine that separates the mechanical transmission of the CD player.
D/A converter: A device that converts digital audio signals into analog audio signals in digital audio products such as CDs and DVDs. The D/A converter can be made as a stand-alone machine for use with the CD turntable, often referred to as a decoder (DAC).
—— Headphones down –
The new headphones that I just got are not very effective, even the headphones that I used for a long time are not as good. This is because the mechanical rigidity of the new earphone diaphragm ring is strong (that is, the compliantness is poor, and the two are inversely proportional). It is necessary to make the piston earphone rigidity deteriorate and the compliantness gradually become better after a period of use (meaning the diaphragm ring) The rigidity is worse, the sound film becomes softer, so that the bass effect emitted by the earphone is gradually improved, and the overall effect will be better and better. In order to make the new headphones work well, we need to take the headset down before using it.
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