Ⅰ. What is speaker?

The speaker is a type of transducer that converts electrical signals to auditory signals. The sound quality is greatly influenced by the speaker's performance. The speaker is the most significant component for audio effects while being the weakest element in audio equipment. There are numerous varieties of speakers available, with a wide range of pricing. Through electromagnetic, piezoelectric, or electrostatic effects, the audio electric energy causes the cone or diaphragm to vibrate and resonant (resonate) with the surrounding air to produce sound.

Ⅱ. The structure of the speaker

Structure of Speaker

A dust cap, a sound cone, a voice coil, a vibrating plate, a basin frame, a binding post, upper and lower magnetic pole components, and magnetic steel make up a loudspeaker.

1. Sound cone

The cone's vibration is employed to cause the air to vibrate, resulting in the sound's heavy death. As a result, the cone's substance influences the speaker's individuality.

2. Basin frame

The following are the types and properties of pot frame materials: Low-cost iron sheet; die-casting: difficult to deform; synthetic material: light weight and difficult to distort.

3. Voice coil stand

The majority of the voice coil frame is made of aluminum sheets. Because the voice coil structure must account for heat dissipation, the aluminum skin provides excellent heat dissipation, is light, and does not distort. It was also available on paper, but that option has since been discontinued. There is also a type of KISV epoxy resin board that performs better.

4. Magnet

Ferrite: The most common and traditional mineral, with big size and low price.

The magnetic of neodymium iron is seven times that of ferrite, but it is unstable and easily demagnetized, therefore it cannot be used in place of ferrite.

Strontium magnets have high efficiency, but because of their small volume, they are exclusively utilized in tweeters.

5. Pieces

The supporting piece, also known as a spring plate or an elastic wave, is used to support the loudspeaker's vibrations. The centering supporting component is made of two major materials: cotton fabric and polyimide fiber.

6. Folding ring

The folding ring connects the cone with the frame, providing support for the cone's vibration mechanism as well as compliance restoration force and dampening effect.

7. Dust cap

The primary purpose is to keep dust and debris out of the magnetic gap. Paper, cloth, aluminum, plastic, or carbon fiber fabric are among the materials utilized. A hemisphere is the most common shape.

Ⅲ. Speaker performance index

Speaker Performance Index

1. Frequency response

The major frequency range in which the loudspeaker operates is represented by this indicator. When a constant voltage signal source is applied to a speaker and the signal source's frequency is changed from low to high, the sound pressure created by the speaker changes with the frequency shift. The greater the range of the resulting sound pressure-frequency curve, the better the sound reproduction properties.

2. Rated impedance

It is the impedance value measured at the speaker's input at a specific operating frequency. The producer usually specifies it on the product's brand nameplate. In the rated frequency range, the rated impedance is usually the impedance modulus at which the highest work is predicted. Rated impedance is commonly stated as 4 ohms, 8 ohms, 16 ohms, 32 ohms, and 3 ohms, 6 ohms, and so on in the United States, and 3 ohms, 6 ohms, and so on in other countries.

3. Power

One of the most crucial factors to consider when selecting a loudspeaker is its power. When a loudspeaker can work continuously for a long time without producing anomalous sound, this is the input power. In most cases, the pink noise signal is utilized in the test, which is run through a specified filter within the rated frequency range.

The rated noise power differs from the maximum noise power. It denotes the loudspeaker's ability to endure high input power for a short length of time. It simply takes a few seconds or minutes to complete the test. The maximum noise power is typically 2-4 times the rated power.

4. Sensitivity

When a pink noise signal voltage equivalent to 1W power on the rated impedance is given to the speaker, the typical sensitivity is measured at 1m in the axial direction. Each speaker unit's sensitivity in the frequency region in which it is responsible for reproduction must be nearly identical in order to balance the high, mid, and bass of the entire speaker during reproduction. The left and right channels of stereo speakers, in particular, must be carefully screened and matched. The output sound pressure level differential of the unit used by the left and right channels must be between plus or minus 1dB, or the sound picture positioning will be affected.

5. Directivity

The ability of a loudspeaker to transmit sound waves in all directions in space is referred to as directivity. The curve of the sound pressure level with the angle of radiation is a common representation. The directivity of a loudspeaker is proportional to its frequency, and at low frequencies, there is usually no discernible directivity. The directivity will become sharp at high frequencies due to the short wavelength of the sound waves. To boost directivity, some speakers place multiple high-frequency components in different directions. The speaker's caliber has an impact on the directivity. In general, the directivity is sharper when the caliber is large; when the caliber is small, the directivity is wider.

6. Distortion

Wave distortion, intermodulation distortion, and transient intermodulation distortion are all examples of speaker system distortion. A speaker's distortion characteristics are more prone to deteriorate than a single speaker's distortion characteristics. Due to poor design or debugging, distortion is usually considerably amplified near the crossover point. Low-frequency harmonic distortion, particularly near the resonance frequency, is the most common source of harmonic distortion. The minimal needed harmonic distortion for high-fidelity speakers is less than 2%.

Ⅳ. How does a speaker work?

Working Principle of Speaker

A speaker's basic idea is to transform electrical energy into mechanical energy (movement). Air is compressed by mechanical energy, which translates motion into sound energy or sound pressure level (SPL). A magnetic field is created as current passes through the coil. Current is passed through the voice coil in the speaker, and the voice coil generates an electric field that interacts with the magnetic field of a permanent magnet attached to the speaker. Charges of the same type repel each other, while charges of different types attract each other. The permanent magnet attracts and repels the voice coil when the audio signal is delivered through it and the music waveform goes up and down. The cone attached to the voice coil moves back and forth as a result of this. Moving back and forth in the air produces pressure waves, which we refer to as sound.

Ⅴ. How to clean the speaker?

How to clean the speaker

1. Take off all the accessories on your hand. If you have a tendency of wearing jewelry or watch accessories, please take them off before wiping the cabinet, since they are prone to scratch it.

2. Use compressed air to blow out the entire speaker cabinet and gently remove any dust that may have gotten inside. Don't underestimate these tiny particles; they're more likely than you believe to harm the paint surface. Other pollutants, such as coarse sand, powder, and even delicate petals, might cause the cabinet to deteriorate. Blowing these things away before wiping helps to avoid inadvertent harm to the cabinet.

3. Two microfiber towels, one of which has been soaked in water and wrung out, and the other which has been kept dry. Soak one of the cleaning cloths in warm water for a few minutes before wringing it out completely. It is not necessary to dampen the other cleaning cloth. Make sure the cleaning cloth you're using doesn't have any creases or thread stitches on it.

4. Wipe the entire speaker cabinet carefully and gently with the fully wrung microfiber towel. It's important not to touch or wipe the tweeter. This is extremely important, so don't touch it.

5. Repeat step 5 with a dry microfiber towel, wiping each section of the box slowly and gently.

What should I do if there are scratches on the speaker cabinet's surface? Although polishing using polishing tools and automotive polishing materials is a regular practice, it is not appropriate for speakers.

First and foremost, the speaker's paint surface is extremely sensitive and quickly damaged. It's difficult to forecast what kind of negative impact the polishing product will have on the paint surface if you don't know the exact chemical composition. Self-polishing by the user almost always results in paint surface damage. As a result, in this scenario, contacting the local distributor to tell them of the product specifics is recommended.

Clean the tweeter

The cabinet for the speakers has been cleaned. How do you clean the speaker's silk soft-dome tweeter? The technique is actually rather simple: simply blow lightly with air.

Before starting to clean up, it's important to remember that you can't touch the silky soft hemisphere tweeter. The silk soft-dome tweeter is a delicate piece of equipment. When cleaning the speaker, you may wish to use a vacuum cleaner or a dust cloth. This is extremely risky because it will almost certainly backfire and harm the speaker.

So, how do you clean a soft hemisphere concave tweeter? If the speaker is playing music, you can disregard the dust on the tweeter.

The small dust on the soft dome tweeter has a negligible impact on the sound quality. If you truly don't like the dust on your tweeter, the best approach to get rid of it is to gently blow it away with an air blower. This should be the safest method of cleaning.

Clean the woofer

The midrange and woofer are more slender than the silk soft hemisphere tweeter. Cleaning can be done with a dry ultra-fine soft fiber cloth. If the woofer has more stubborn stains, you can remove them with a moist cloth that has been thoroughly wrung out, and then gently wipe them away with a dry cloth to finish the cleaning process.

Cleaning the speaker is a complicated process. It needs a great deal of patience and care, and the best procedure is determined by the distinct features of the individual speaker units. In everyday life, everyone must be aware of the importance of preserving speakers against harm.