Xiaomi Redmi Note 9 is one of the most popular smartphones in the budget segment, but many users face the problem of insufficient volume of speakers or headphones. Quiet sound during calls, indistinct speech in messengers or weak music through the column can seriously spoil the impression of the device. In this article, we will discuss all possible ways to amplify the sound from basic settings to hidden functions of the engineering menu and third-party applications.
It is important to understand that the volume limits on the Redmi Note 9 are often related to the hardware features of the model: there is one monophone speaker with a power of about 0.8 W, which is objectively weaker than that of flagships with stereo systems. However, software methods allow you to squeeze the maximum from the existing hardware without the risk of damaging the speaker. We tested all the methods described below on MIUI 12.5-14 firmware (including global and European versions), so the instructions are relevant for most users.
1. Checking basic volume settings
Before you resort to radical measures, make sure that the problem is not the basic settings.The Redmi Note 9 has separate volume controls for different types of sound, and often users simply do not notice that one of them is twisted to a minimum.
Open the Quick Settings Panel (swipe down from the top edge of the screen) and check:
- 🔊 Total volume is a slider in the top right corner, and it regulates the sound of notifications and system signals.
- 🎵 Media: It appears when you play music or video, and it's responsible for the volume in the apps.
- 📞 Calls -- activates during a conversation. Controls the volume of the tube.
If the sliders are at maximum, but the sound is still quiet, go to Settings → Sound and vibration → Volume and manually adjust each setting. Pay attention to the item "No sound" - if it is activated, all other settings will be blocked.
⚠️ Attention: On some firmware MIUI There's a bug where resetting the audio settings to the factory settings causes user profiles to zero. → Additionally. → Backup.
Activation of the "Sound Amplifier" mode in MIUI
MIUI firmware for Redmi Note 9 has a built-in audio amplifier that can be turned on without root rights, which increases volume by 15-20% due to software signal processing, but can slightly worsen the sound quality (the appearance of wheezing at maximum volume).
To activate the amplifier:
- Open the Settings app.
- Go to Sound and Vibration → Additional settings.
- Find the item "Sound Amplifier" (on some firmware it is called "Sound Improvement").
- Activate the switch and select the Music or Conversation profile depending on the task.
If the item is not on the menu, try an alternative way:
- 🔧 Enter the code in the phone application: ##36446337##
- 🔊 In the Engineering Menu, select Hardware Testing. → Audio → LoudSpeaker Mode.
- 📊 Set the value of "Level 5" (maximum gain).
Check the current version of MIUI in Settings → About the phone
Take a screenshot of the current sound settings
Battery charge should be above 30%
Do not interrupt the process of changing parameters.-->
3.Use of the engineering menu for manual tuning
The engineering menu on the Redmi Note 9 allows you to manually increase the volume of the speaker to 120% of the factory values, but this requires caution - incorrect parameters can lead to a distortion of the sound or overload the speaker.
Instructions for setting:
- Open the phone app and enter the code: ##4636##
- Select Information → Audio from the menu.
- Scroll to the Loud Speaker or Headset box.
- Change the settings: Max Vol: 150 (maximum) Min Vol: 0 (do not change!) Current Vol: 100 (base value)
Set
| Parameter | Factory importance | Recommended value | Maximum permissible |
|---|---|---|---|
| Max Vol (dynamics) | 128 | 140 | 150 |
| Max Vol (headphones) | 100 | 110 | 120 |
| Mic Gain (microphone) | 4 | 5 | 6 |
⚠️ Note: Set the value of Max Vol = 150 for the speaker can cause distortion at high frequencies and shorten the life of the membrane.We recommend starting with 140 and testing the sound on different tracks.
4.Apps for amplification of sound (without root)
If the standard methods didn't work, you can use third-party applications. We tested 5 popular utilities and selected the two most effective for the Redmi Note 9:
1. Volume Booster GOODEV (free, no advertising)
- 📱 Increases volume by 30-40% due to software amplifier.
- 🎛 It has separate regulators for speaker, headphones and Bluetooth.
- 🔧 Supports custom presets for different scenarios (music, games, calls).
Download from Google Play and activate Max Boost mode after installation.
2. Equalizer & Bass Booster (from Sony)
- 🎵 Built-in 10-band equalizer for fine-tuning frequencies.
- 🔊 Bass Boost enhances low frequencies without distortion.
- 🎧 Supports individual profiles for headphones and dynamics.
The app is officially from Sony, so it's conflict-free MIUI compatible.
💡
Before installing third-party sound amplifiers, turn off the built-in amplifier in MIUI (see section 2) to avoid overlaying effects and distortion.
5. Equalizer adjustment to improve perception
Sometimes the problem is not the volume level, but the wrong frequency balance. For example, if the Redmi Note 9 has too high frequencies, the sound seems quieter due to the imbalance, in which case the system equalizer will help.
How to set up:
- Open Settings → Sound and vibration → Equator.
- Choose presets like Rock or Pop, which are optimized for maximum volume.
- Manually lift the sliders at 100 Hz and 300 Hz (low frequencies) by +3 dB.
- Reduce the slider by 8 kHz (high frequencies) by -2 dB to reduce hissing.
For accurate settings, use test tracks:
- 🎶 Low frequency test (20–200 Hz)
- 🎵 High frequency test (1–20 kHz)
How to reset the equalizer settings to factory?
6. Cleaning dynamics from dust and debris
Physical contamination of the speaker is one of the most common causes of volume loss. On the Redmi Note 9, the speaker hole is located on the bottom of the device and is often clogged with dust, villi from the pocket or particles from the case.
How to clean the speaker:
- 🧹 Use a soft toothbrush (dry!) to remove visible debris.
- 💨 Blow the speaker hole with compressed air (a balloon for cleaning equipment).
- 🎵 To check, play the test sound: ##0283## (turn on the speaker test at maximum volume).
If the sound has not improved after cleaning, the problem may be damage to the speaker membrane, in which case a replacement module will be required (cost ~ 800-1200 rubles in the service center).
⚠️ Warning: Do not use wet wipes, alcohol or metal objects to clean the speaker! Getting liquid on the contacts or damaging the speaker mesh will lead to irreversible breakage.
7.Alternative methods: from Bluetooth amplifiers to external speakers
If the software methods didn't help, consider hardware solutions. Here are some proven options for the Redmi Note 9:
1. Bluetooth sound amplifier
- 🎧 Devices like FiiO BTR3 or SoundMagic ES100 connect via Bluetooth and amplify the signal before transfer to headphones.
- 🔋 It lasts up to 10 hours from the battery.
- 🎛 Have built-in equalizer and support for aptX for high sound quality.
External column with AUX-entrance
- 🔊 Connect your phone to a portable speaker via a 3.5mm connector (on the Redmi Note 9, it is there!).
- 🎵 Even budget models like Xiaomi Mi Portable Speaker sound louder than the built-in speaker.
- 🔋 Columns with power from 5 W will provide comfortable listening indoors.
3. Active noise cancellation (ANC) headphones
- 🎧 Models like Xiaomi Hybrid ANC or Soundpeats Air3 Block external noises, allowing you to listen to music at lower volumes.
- 🔋 ANC-Headphones consume more power, but the Redmi Note 9 with a battery of 5020 mAh easily copes with the load.
💡
Hardware solutions (external speakers, amplifiers) are better than software, but require additional investment, and the best option is to start with free methods (sections 1-5), and then consider buying accessories.