How to remove low frequency noise from Bluetooth speakers?

Look at whether the front is with a battery or a transformer, or a switching power supply. In fact, the power amplifier circuit has the highest power supply requirements. To be very clean, the ideal is to use battery power, but in many places, it is impossible to use batteries, so it is still necessary to use power supply.

If so, it's good to be sure it's a power supply issue. Change the power supply. I do not need this kind of pulse voltage conversion IC.

It is best to use a low-frequency transformer to transform the voltage.

If conditions permit, the effect of installing a shielding cover for the transformer is very obvious, which can block the magnetic leakage to the greatest extent, and the shielding cover can only be made of iron materials. Generally speaking, we should try to choose big brands, solid materials products, if the transformer core, copper wire and other materials are of poor quality, the transformer's iron loss and copper loss will be more serious, resulting in the transformer's no-load current increase, then the magnetic flux leakage phenomenon will be more obvious, in addition, the use of external transformers is also a good way.

See if there is interference around, take it out of an open place outside, use the Bluetooth of your mobile phone to connect this speaker to try, see if there will be noise, buy a blocker.

There will be noise when the battery is about to run out, so change the power supply. In fact, the public circuit has the highest requirements for power supply, and it must be very clean, and it is easy to determine that it is a power supply problem.

Is there a big electrical appliance nearby There is interference If not, it is a problem of things, it is best to use a low-frequency transformer to transform the voltage, if so, do not want this kind of pulse transformer IC, or switching power supply.

Most likely, the horn is broken. It is also possible that some parts are loose, and the sound is emitted by vibration. I took it apart, and because it was a hexagonal screw, I thought it was broken, so I just tightened the screw.

250px can hear the sound of current is not strange,Many speakers are also like this,If you want to paste it to hear it, it means that the workmanship is very good,It is estimated that it is not cheap,Even tens of thousands of amplifiers will still sizzle when you go to listen to it。

You can choose to restart the speaker or mobile phone, and then relink to check whether the speaker has dust.

It may also be caused by a low battery, so use an external power adapter to test it. If the power is low, charge or replace the battery in time, don't ignore it.

The ideal is to use battery power, which is the most ideal, it is impossible to use batteries, there is no input signal and current sound, so it is still necessary to use power supply, battery sound, rectifier filter power supply.

My family sells Bluetooth speakers,How to remove low-frequency noise from Bluetooth speakers,In fact, I think the biggest problem is the quality of Bluetooth speakers,If you buy a cheap Bluetooth speaker,In fact, there will be no good sound effect,If it**high,*** speaker,That's no problem。

As long as you don't turn on the sound too much, it won't disturb the people, and it is recommended not to use it at night.

Because the sound of the subwoofer is very loud, it travels far and will produce a certain vibration wave, which causes the windows and doors on the floor to shake. Therefore, do not use the subwoofer in an open place, the sound has a wide range of transmission, and the vibration is still very strong.

When using a subwoofer at home, you should also pay attention to the time period and volume, so as not to disturb the people. The sound of this kind of audio is particularly bright when the bass is low, and the volume is transmitted very far, so it is not recommended to use it at high volume.

Subwoofer definition.

Subwoofer is a common name or abbreviation for everyone, strictly speaking, it should be: subwoofer. Heavy bass means super bass in English, that is, bass with heat and energy.

As the name suggests, the role of the bass is to strengthen the bass band, that is, to enhance the long-wave part of the audio (below 100Hz, even including infrasound, although people can't hear it, but it still has an effect), because ordinary speakers have a limited volume and cannot emit low-frequency sounds of longer wavelengths, so a larger volume of subwoofers is needed to produce a low-frequency warm effect.

The concept of "subwoofer" was innovatively developed for the first time, and the term "subwoofer", a local characteristic, was pioneered by Mai Lan (now Mai Bo). This statement is more down-to-earth, because its ** effect is as warm and cheerful as firecrackers during the Spring Festival, full of enthusiasm, fiery and hot, so it is commonly known as "subwoofer".

Turn the volume of the volume potentiometer to the lowest that is, silent, there should be no sound at this time, if there is a hum sound, then Xiangqiling is caused by the change of the capacity of the electrolytic capacitor in the filter circuit of the power amplifier, which is too small; If you turn on the loud sound, there is a big humming sound, which is caused by the poor shielding of the audio input of the power amplifier, check and eliminate the shielding fault.

other solutions; Side letter.

The shell of each element must be grounded, and the audio input line must be shielded and well grounded.

The horn hisses, and most of the problems encountered in this situation are caused by poor shielding of the body, or the primary stage of the power transformer winding is not well isolated. The solution is actually very simple, that is, just turn the power plug around, if it doesn't work, connect two 4700p capacitors in series at the power input end (the power input end of the transformer), and connect the center tap to the casing, which can be eliminated, or due to the poor shielding of an audio input terminal.

How to eliminate the bottom noise of Bluetooth headphones.

Taking Xiaomi Bluetooth headset Air2 SE as an example, the bottom noise of Bluetooth headset cannot be eliminated, and the low noise of Bluetooth headset is caused by interference in the process of Bluetooth wireless signal transmission, which is a common phenomenon in Bluetooth headsets.

If the phone's decoder chip produces a slight noise floor during the audio parsing process, then you can go to the phone's "Settings" function, then turn on the "Developer Options" function, then click on "Bluetooth LDAC Encoder", and finally select the "Provide the best possible sound quality" option, which can reduce the noise floor as much as possible.

There are some cheaper Bluetooth headsets due to the optimization of the chip and the poor anti-interference ability of the Bluetooth signal are more prone to noise floor, and the noise floor of generally higher products will be relatively slight, if the noise background is too large, it will affect the effect of your listening.

The noise floor is the background noise, which generally refers to the total noise in the electroacoustic system except for the desired signal.

If we want to detect how much noise floor there is in our headphones, then we need to put on headphones in a relatively quiet space, **** file and turn the volume to as low as possible (generally volume 1, or just enough to appear ** sound), we can hear a subtle rustle, which is the floor noise.

Professional method of detecting noise floor: use audio software to generate a blank waveform file, that is, a completely silent file, and then turn the volume of the device to the maximum, record the decibel of the noise floor, and generate relevant professional data.

1. It cannot be completely eliminated, the low noise of Bluetooth headset is caused by interference in the process of Bluetooth wireless signal transmission, which is a common phenomenon of Bluetooth headset, and the decoding chip of the mobile phone will also produce a slight noise floor in the process of analyzing audio.

2. There are some relatively cheap Bluetooth headsets that are prone to noise floor due to the optimization of the chip and the poor anti-interference ability of Bluetooth signals. If the noise floor is too large to affect the effect of your listening**, you can try using an adapter cable to use Bluetooth headphones.

Generally speaking, computer audio is mostly active speakers, and there will be an amplifier inside, so noise is inevitable, and the noise of active speakers can be roughly divided into electromagnetic interference, mechanical noise and thermal noise.

Electromagnetic interference can be mainly divided into power transformer interference and stray electromagnetic wave interference. Generally speaking, the power transformer interference is caused by the power flux leakage of the multi-speaker speaker, and the effect of installing a shielding cover for the transformer is very obvious when conditions permit, which can block the magnetic leakage to the greatest extent, and the shielding cover can only be made of iron materials. We should try to choose products with big brands and solid materials, and in addition, using external transformers is also a good solution.

Stray electromagnetic interference is common, and speaker wires, crossovers, wireless devices, or computer hosts can all become sources of interference. Keep the main speaker as far away from the computer as possible and reduce the number of peripheral wireless devices.

Mechanical noise is specific to active loudspeakers. During the operation of the power transformer, the core vibration caused by the alternating magnetic field will produce mechanical noise, which is very similar to the humming sound emitted by the fluorescent lamp ballast. Choosing the best product is still the best way to prevent this noise.

In addition, we can add a rubber shock absorber between the transformer and the fixing plate.

It should also be noted that if the potentiometer is used for a long time, the contact between the metal brush and the diaphragm will be poor due to dust accumulation and abrasion, and noise will be generated when it rotates. If the screws of the speaker are not tightened, and the inverter is not handled properly, mechanical noise will also be generated when the **big dynamic**.

This thermal noise can be dealt with by replacing low-noise components or reducing the working load of the components, and reducing the operating temperature is also one of the most effective methods.

In addition, some computer speakers, when the volume is turned up too much, there will also be noise. This situation is caused by the fact that the output power of the power amplifier may be small, and it cannot avoid the large dynamic peak signal at the moment, or because of the overload distortion of the horn.

First, first confirm that the hardware is fine. If the speaker is fine, the sound card is fine, and if you've tested it on other machines and it's really good, then you can read on.

2. Make sure all the cables are exactly right. Then power on the speaker and turn on the volume switch.

3. Install the driver of the sound card correctly, if it is an onboard sound card, it is best to install the driver provided on the driver disk of the motherboard.

In fact, the computer does not make a sound, and many times it is because the sound card is not driven correctly. In general, after the sound card driver is installed, there will be a small speaker icon in the taskbar in the lower right corner. ）

Fourth, if you are sure that the driver is installed correctly, then take a look at the volume settings in the computer.

The specific method is to double-click the speaker icon in the taskbar, and check whether the volume is turned off to the minimum in the "Volume Control" and "Waveform" dialog box in the pop-up "Volume Control" and "Waveform".

If these two options are not available in the dialog box, click on the "Options" menu - select "Properties" - select "Volume Control" and "Waveform" in the "Show Volume Controls" and then set them correctly.

Note: Step 4 can only be set up after the driver for the sound card has been installed correctly.

Generally speaking, the sound should not be used for a long time, and the noise when used again should have the following aspects:

1. If the volume potentiometer is in contact with the problem, you can clean the potentiometer with anhydrous alcohol, rotate it while cleaning, until the alcohol flowing out does not contain impurities, and it can be used after cooling.

2. Oxidation of connectors. Clean it from the inside to the outside to remove the oxide layer.

3. Oxidation of external connectors, cleaning method as above.

4. The components are damp, this problem needs to have a certain electronic basis, find the bad parts, replace them, sometimes the transformer will heat up when wet, and the moisture will be driven away with the increase of the use time.