How the microphone in the smartphone Xiaomi: schemes, problems and secrets of quality recording

Ever wondered why your Xiaomi is so clear in its voice while recording noise-like videos as if you were standing in a tunnel? Or why the phone drops and suddenly stops hearing you? The answer lies in the microphone, one of the most underrated but critical components of modern smartphones. In this article, we will examine the physical design, electronic circuitry and software processing of microphones in Xiaomi, Redmi and POCO devices, and find out why even flagships like the Mi 13 Ultra sometimes have problems with sound.

The microphone in a smartphone is not just a hole on the body. It is a complex system of several sensors, amplifiers and noise reduction algorithms that work in sync with the processor and the operating system. For example, the Xiaomi 12T Pro uses three microphones: one for voice calls, one for recording video, and the third for active noise cancellation, each with unique locations and characteristics. Next, we will discuss in detail how this works, what types of microphones are in Xiaomi smartphones, and what to do if the sound is lost or worsened.

1. Types of microphones in Xiaomi smartphones: MEMS vs. electret

Most modern smartphones Xiaomi are used MEMS-Micro-Electro-Mechanical Systems, but you can still see outdated electrets in budget models:

• 🔬 MEMS-Microphones: miniature (sized as a grain of sand), low energy consumption, resistant to moisture and vibration. 11/12/13, Redmi Note 10 Pro+ newest POCO F5.
• 🎤 Electric microphones: cheaper but sensitive to mechanical damage and humidity, found in older models like the Redmi 7A or Mi A3.
• 🔇 Digital vs. analog: Xiaomi flagships are equipped with digital MEMS-microphones with built-in ADC (analog-digital converter), which reduces signal loss.

The main advantage of MEMS is the built-in protection against acoustic shock (sound overload), which is especially important for smartphones with powerful speakers. For example, in Xiaomi Mix Fold 3 microphones can withstand sound pressure up to 130 dB without distortion, while the electret begin to “hackle” at 110 dB.

⚠️ If after a loud concert or firecracker explosion, the microphone in your Xiaomi stopped working, it most likely went out of order. MEMS-The sensor will cost 1500-3,000 rubles to replace it at the service center.

Interesting fact: the Xiaomi 13 Pro uses a microphone from Knowles (model SPM0428LE4H) - the same manufacturer that supplies components for the AirPods Pro. This provides record-low noise level (up to 62 dB) and a wide frequency range (50 Hz - 20 kHz).

Location of microphones: where to look and how to check

Xiaomi smartphones have microphones in three standard zones, but the number varies depending on the model:

1. The bottom microphone (main for calls) is next to the USB-C connector or 3.5 mm (older models) and is responsible for transmitting voice during a conversation.
2. The top microphone (for noise reduction) is next to the speaker speaker (above the screen) and is used to suppress echoes and backgrounds.
3. The rear microphone (for video) is next to the main camera, and some models (for example, the POCO X5 Pro) do not have it, instead using the top camera.

To check which microphone is currently working, follow the following steps:

Launch the Dictaphone app and record the sound, closing the microphone holes with your finger in turn.|Call another phone and check how the sound changes when you close the bottom/top microphone.|Use the engineering menu: type ##4636##, select Audio → Microphone Test|Install the Microphone Test app from Google Play for detailed diagnostics-->

Stereo-recorded models like the Xiaomi 12S Ultra use two microphones at once, one in front and one in the back, which allows you to create surround sound in video, but requires precise calibration in the factory.

⚠️ Warning: If the bells are missing after replacing the display or back cover, check to see if the wizard is damaged by the flexible plume connecting the microphone to the motherboard! 3. Microphone in Xiaomi smartphone connects to the motherboard via an audio codec - a specialized chip that converts analog signal to digital: 🔊 Qualcomm WCD9385 — in smartphones on Snapdragon 8 Gen 1/2 (for example, Xiaomi 13 Pro). Supports 32-bit-based audio stream and hardware noise-canceling. 🎛️ Realtek ALC5682 — In budget models on MediaTek Helio (for example, Redmi) 10A). Simpler but less energy efficient. 🔌 Direct SoC connection – In some models, the microphone connects directly to the processor (e.g., in the POCO M5), This saves space on the board, but increases the load on the CPU. The standard connection scheme looks like this: Microphone → amplifier (if signal is weak) amplifier → ADC (analog-to-digital converter). ADC → audiocode → processor. → Noise reduction algorithms (e.g. Xiaomi Noise Cancellation) in flagships like Xiaomi 13T The Pro uses dual ADCs, which allow you to process signals from two microphones in parallel, improving the quality of stereo recording. K60 Pro added a separate amplifier for the bottom microphone to improve voice transmission in noisy conditions.What is an "acoustic camera" in Xiaomi microphones? Some models (such as the Xiaomi Mix 4) have microphones in miniature acoustic cameras, sealed compartments that protect them from wind and dust, which increase the cost of production by 15-20%, but reduce noise by 30% compared to open microphones. If you take apart a smartphone and see a small capacitor or inductor next to the microphone, it is part of a lower-frequency filter that cuts off high-frequency interference (for example, from a low-frequency filter). 5G-4. Sound processing software: how Xiaomi improves voice The hardware part is only half the success.The real sound quality depends on the software algorithms that Xiaomi integrates into the firmware MIUI. Here are the technologies used: 🔇 AI Noise Cancellation — the neural network analyzes background noise (wind, transport, voice) and suppresses it in real time. MIUI 13+. 🎙️ Voice Focus – highlights the voice of the user even in noisy environments (for example, at a concert). 12/13 series. 📱 Dual-Mic Recording – uses two microphones simultaneously to create directional sound (as in professional loop microphones). 🔊 Adaptive EQ — It automatically adjusts the equalizer to the user's voice (for example, makes it more "bass" for male voices). An interesting nuance: in Xiaomi, noise reduction algorithms work differently depending on the application: - In Calls, aggressive background suppression is used. - In the recorder - softer, to preserve the naturalness of the sound. TikTok/Instagram — Special profile for high-frequency social networks. To enable or disable these features, go to: Settings → Sound and vibration → Improvement of microphone sound. 💡After the update MIUI You've lost the microphone, reset the sound settings to the factory. → All parameters. → Resetting settings → 5. Typical microphone problems and solutions Even in the most reliable Xiaomi smartphones, microphones can fail. Here are the most common problems and ways to fix them: Problem Possible cause Solution The interviewer doesn't hear you in calls Contaminated bottom microphone or damaged plume Clean the hole with a needle or compressed air. If it doesn’t work, replace the microphone (~1500 RUB.) Noise when recording video Faulty rear microphone or switched off noise cancellation Enable microphone sound improvement in the settings of the camera Echo in the headset Conflict with Bluetooth codecs (for example, aptX) Switch to SBC in Bluetooth settings The microphone works only on the speaker Damaged top microphone (responsible for noise reduction) Diagnostics in the service center (replacement of the microphone) ~2000 RUB.) If the microphone stopped working after falling or getting moisture, do not try to dry it with a hair dryer - this can damage MEMS-membrane. Instead: Turn off your smartphone immediately and remove it. SIM-map|Place the device in a silica gel package (at least) 24 hours)|Do not turn on until you make sure that the moisture has completely evaporated.|If the microphone does not work after drying, contact the service--> In Xiaomi with IP53/IP68 The microphones have an additional hydrophobic membrane, but it does not guarantee that they will be able to 100% For example, in the Redmi Note. 11 Pro+ 5G After immersion in water, the microphone fails in 30% case. ⚠️ Warning: If you notice that the microphone starts to "wheez" or distort its voice after installing custom firmware, the problem is with the audio codec drivers. MIUI Or find a firmware with corrected audio_blobs. 6. How to improve the sound quality of the microphone in Xiaomi Even if the microphone is good, the sound quality can be improved software and hardware. Here are a few proven ways: 🎤 Use an external microphone: USB-C or 3.5 mm (if there is a connector, BOYA BY-M1 worth ~2000 rubles and gives studio quality. 📱 Set up the equalizer: in Settings → Sound. → Select Preset Voice or create your own with 2-4 kHz amplification. 🔇 Turn off unnecessary effects: some functions like 3D Sound can impair voice transmission. 🔊 Update the firmware: in new versions MIUI They often improve noise reduction algorithms. MIUI 14 added support LDAC For streamers and podcasters, it is useful to install applications like Wo Mic or Microphone Pro that allow you to: - Adjust voice compression (to make it sound louder). - Remove background noise in real time. - Use your smartphone as a voice compression. USB-pc-mic. Xiaomi 13 Pro and later has a hidden Super Voice feature that is activated via the engineering menu: ##847## → Audio → Super Voice Mode → It improves voice transmission in networks with poor signal (for example, in the subway). 💡If you want professional sound quality, you better use an external microphone. MEMS-Xiaomi microphones are good for everyday tasks, but will not replace specialized equipment. 7. Repair and replacement of microphone: when to contact the service If the microphone in your Xiaomi finally fails, it can be replaced. Cost and complexity of repair depend on the model: Model Replacement cost (ruble) Complexity of repair Xiaomi Notes 13/13 Pro 2500–3500 Middle soldering station required to detach the Redmi Note plume 12 Pro+ 1500–2000 Low Microphone on a separate module, easy to replace POCO F5 1800–2300 You need to remove the motherboard Xiaomi Mi 11 Lite 1200–1700 Low Electret microphone, cheaper than analogues Self-replacement is possible, but requires: T3–T5 and Phillips 000. - Plastic blades for opening the case. - Dryer or stations for warming up the glue (in models with a waterproof body). 10 Pro: Turn off the phone and remove the back cover (warming up the edges with a hairdryer). Unplug the battery (required!) to avoid short circuit. Find the microphone (near the connector). USB-C) And you can sell it off with a thin stinger iron. Install a new microphone (like the Original Xiaomi Microphone for Redmi Note 10) and assemble the phone in reverse order. ⚠️ Attention: In models with IP68 (For example, Xiaomi 13 Ultra) after self-repair, water resistance is lost! To restore protection, you will need to replace glue and gaskets (~1000 rubles in the service). FAQ: Why Xiaomi has two microphones but only one? In most Xiaomi models, the second microphone is used only for noise reduction or stereo recording. During a normal call, only the bottom microphone works. To use both, turn on Dual-Mic in the camera or voice recorder settings. Can you clean the microphone with alcohol? No! Alcohol can damage the hydrophobic membrane in the microphone? MEMS-Use a dry brush or compressed air to clean the microphone, and if the microphone is heavily polluted, you should contact the service. Why After Updating MIUI Is there a problem with the microphone update? OTA. Solution: Reset the sound settings: Settings → All parameters. → Resetting settings → Reset the audio settings. If it doesn't work, run the phone through the Mi Flash Tool with a full clean (clean all). How to check if the microphone on Xiaomi works without a call? There are several ways: Use the built-in recorder and check the recording. Enter the engineering code ##4636## → Audio → Microphone Test. Install the Microphone Test app from Google Play. Which microphones are better: Xiaomi or Samsung? In flagship models (Xiaomi 13 Pro vs. Galaxy) S23 Ultra) microphone quality is comparable - both use MEMS But Samsung has better optimized noise cancellation for voice calls, and Xiaomi is winning in video recording thanks to Dolby Atmos support.