Buy now
KZ Knowledge Zenith logo
Knowledge Zenith
Bluetooth 5.3 Ear hooks
Upgrade wired earphones to wireless earphones
Buy now


Essential wireless accessory for audiophiles
Qualcomm QCC5171 wireless ear hook
Bluetooth 5.3
Snapdragon Sound Technology
aptX HD Audio Lossless Decoding
Three Original Performance Modes
Long-lasting Battery Life
Zero Perceptible Latency

Is the sound quality of your wireless earphones poor?

Then it must be that its Bluetooth chip needs to be better!
Suppose you want to enjoy the convenience of wireless headphones and desire satisfying sound quality. In that case, we can responsibly tell you that replacing your play device with one that uses a high-end Bluetooth chip is the best way. KZ AZ20 uses a QCC5171 chip.
Parameter comparison
Power consumption
Transmission bitrate
Transmission protocol
Call noise reduction technology
Bluetooth version
1. CD Lossless and high-resolution audio LEAudio
2. Kalimba™ audio DSPs
3. Dual 240 MHz Qualcomm©
4. aptX Adaptive
5. aptX HD Audio
6. aptX
7. SBC
8. AAC
CVC 9.0
1. aptX HD Audio
2. aptX
3. SBC
4. AAC
CVC 8.0
1. aptX
2. SBC
3. AAC
CVC 6.0
1. SBC
2. AAC
1. SBC
2. AAC
B*S 26**
1. SBC
2. AAC
Note: The above data only represents the functions this chip supports and does not imply that products equipped with this chip have all these functions.The above data only represents laboratory test data and is for reference only.

Restore the original sound quality

Bringing you the purest and most beautiful listening experience
In the audio field, the higher the sampling frequency, the denser the information captured, and the larger the amount of sound information, the more accurate and natural the sound reproduced. The higher the bit rate (bit), the more data is transmitted per second and the clearer the sound.The 24bit 384kHz QCC5171 can achieve is already the pinnacle of wireless audio technology.
KZ AZ20 inside
Sampling rate
Bit rate
Sound quality
QCC5171 24bit 384kHz
Other 24bit 96kHz

Let strength speak, no bluffing

Many articles are introducing the Qualcomm 5171 chip. Still, it's impossible to find another chip from brands other than Qualcomm that can rival it because it is currently the pinnacle of Bluetooth chips.
Qualcomm 5171 chip

Say goodbye to bottom noise and current noise

The ultra-high signal-to-noise ratio of the QCC5171 can cover the frequency response curve of Hi-Fi earphones. Even under high power output, it can maintain a clean background sound, providing an unparalleled auditory feast.
Signal-to-noise ratio: 105.1dB
QCC 3020
Signal-to-noise ratio: 100dB
Signal-to-noise ratio: 98dB
Signal-to-noise ratio: 90dB

All as top performers in the wireless industry

The sound quality / Call performance / Overall performance / Power consumption
Regarding sound quality, the Qualcomm aptX Adaptive technology allows wireless transmission of high-definition audio at 24-bit 48kHz and 24-bit 96kHz. QCC5171 supports the latest aptX Lossless, providing CD-quality 16-bit 44.1kHz lossless audio. With aptX Voice technology, Snapdragon Sound can also support end-to-end Bluetooth Ultra-Wideband (UWB) voice. With a 32kHz sampling frequency, it delivers a smooth frequency response sound of up to 16kHz. This will bring high-quality voice calls to your earphone.

Apart from sound quality, Snapdragon Sound offers other remarkable features. With the rise of mobile gaming and short video platforms, the increased usage time for gaming and video watching has highlighted latency issues' impact on headphone usage. The low-latency transmission of aptX Adaptive can provide a gaming mode with audio latency as low as 68ms.

Furthermore, Snapdragon Sound utilizes Qualcomm High-Speed Chain Modulation technology to achieve a 4dB gain and Qualcomm aptX Adaptive technology to achieve a 2dB gain. Reducing retransmissions and shortening broadcasting time better supports Wi-Fi coexistence and delivers a more powerful overall connectivity experience.

Advanced modulation and encoding technologies contribute to faster end-to-end Bluetooth connections, improved range, stability, and resistance to interference.

Combined with the advanced process of QCC5171, music playback power consumption can be as low as 4mAh, significantly enhancing battery life.

In summary, Snapdragon Sound technology aims to enhance the user experience with wireless earphones, allowing users to experience wireless audio quality on par with wired audio.

Regarding call quality, Snapdragon Sound integrated into QCC5171 features Ultra-Wideband (UWB) call technology, allowing for voice signal transmission with a 32kHz sampling rate over standard Bluetooth. This significantly improves the sound quality during Bluetooth calls and reduces environmental noise, enhancing the user experience.While standard Bluetooth calls typically provide a frequency response of 4kHz, and wideband calls offer 8kHz, Snapdragon Sound delivers a frequency response of 16kHz.

This means that the call quality provided by Snapdragon Sound can cover the entire range of sounds humans can hear. Generally, the human hearing range falls between 20Hz to 20kHz, with very few people able to hear sounds above 18kHz, and even fewer beyond 15kHz. Thus, Snapdragon Sound's call quality can encompass the majority of sounds that humans can perceive, providing a higher quality experience during calls.

Plug and instantly transform wired earphones into wireless

With just a simple plug and unplug, you can quickly transform your wired earphones into professional wireless earphones
KZ AZ20 allows you to enjoy music with wireless freedom. Experience the convenience and flexibility of wireless audio and enjoy your favorite tunes without the hassle of tangled wires.
How to transform wired earphones into wireless with KZ AZ20
*The earphones shown in the image are only for demonstration purposes and are not included in the product.

Extremely meticulous ergonomic design

KZ AZ20 boasts an exceptionally meticulous ergonomic design crafted based on extensive research of the human ear contours over the years. The ear hook is made from skin-friendly silicone gel and is pre-molded to ensure a perfect fit. This thoughtful design offers a lightweight and comfortable experience, allowing extended wear without feeling pressure or discomfort. The ear hook fits snugly around the ear contours, ensuring a secure fit that minimizes the risk of the earphones falling off during use.
*The earphones shown in the image are only for demonstration purposes and are not included in the product.
KZ AZ20 with KZ AS24 on the ear

Superior comfort with 30% smaller and lighter ear hooks

Compared to other competing Bluetooth ear hook products, KZ AZ20 stands out with a remarkable 30% reduction in ear hook volume and a lighter overall weight. This makes KZ AZ20 more compact, lightweight, and convenient to wear.
B*30 size chart
Model Name: B*30
Dimensions: 52mm*13.6mm
Weight: ~8g
KZ AZ20 size chart
Model Name: KZ AZ20
Dimensions: 54mm*10mm
Weight: ~4.9g
Ut*S3 size chart
Model Name: Ut*S3
Dimensions: 56mm*15.2mm
Weight: ~6.5g
Note: The above data is manually measured and may have slight variations.

Gaming Mode / Balanced Mode / Bass Boost Mode

With these three original performance modes, KZ AZ20 allows you to customize your audio experience based on your preferences and the type of content you are listening to, making it a versatile and high-quality Bluetooth ear hook.
KZ AZ20 left and right
Bass Boost Mode
Enhances the bass frequencies, delivering a more powerful and impactful low-end audio experience for bass enthusiasts and music lovers who enjoy deep, rich tones.
Gaming Mode
KZ AZ20 is optimized for gaming, providing low audio latency. It offers a well-rounded and balanced audio output and a responsive audio experience for an immersive suitable for various audio content, including music and gaming session.
Balanced Mode
KZ AZ20 offers a well-rounded and balanced audio output, suitable for various audio content, including music, videos, and general daily use.

Ultra-long and enduring battery life

The KZ AZ20 ear hooks provide approximately 6 hours of playback on a single full charge. Combined with the charging case, the total battery life is about 54 hours. This extended battery life ensures you can enjoy your music and audio content freely, anytime and anywhere, without worrying about frequent recharging.
KZ AZ20 in the charging case
Single full charge battery life
Total battery life with charging case
Charging case battery capacity

Comparison of power consumption and battery life

* Under the same battery capacity of 35mAh
Power consumption: 4mAh
Power consumption: 8mAh
Power consumption: 8-15mAh
QCC 5171
QCC 3040
Other chips
Battery life: ~6 hours
Battery life: ~3 hours
Battery life: ~2-3 hours
Note: This data represents test results conducted in a laboratory setting and is only provided for reference.

Simple, practical, and environment-friendly packaging

Products do not need to be packaged in luxury because the actual performance of products can not be presented in packaging. We advocate environmental protection, but we will not make high profits in the name of environmentalism, which has been one of the beliefs of KZ since its founding.
KZ AZ20 with package

Product Information

Product Model
Bluetooth Version
Charging port
Bluetooth Range
Earphone playing time
~6 hours
Charging case battery capacity
Earhooks battery capacity
Supports extra recharging times
~9 times
 KZ AZ20 next to charging case
Contact information
Service Hours:9:00-21:00
Service Hotline
B2B cooperation
2nd Floor, Building A, Longchang MicroPort Park, No.26 Hantang Street, Gutou Community, Dongcheng, Dongguan, Guangdong, China