Maxhub BM31 — testing a premium HD speakerphone
Maxim Liadov
Our readers know Maxhub from our reviews of the Maxhub BM21 — a premium business speakerphone and Maxhub BM41 — the new flagship speakerphone. The manufacturer is CVTE Group, a large Asian company with 20 years of experience designing and making high-tech products for business, education, medicine, and system integration. Its original designs are reliable and high quality. They have proved themselves and compete successfully with leading brands.
The new Maxhub BM31 is an HD speakerphone for demanding users in business, education, and other fields where sound quality and functionality come first.
The Maxhub BM31 has an impressive feature list:
- Array of 8 microphones
- Microphone pickup range: 6 meters
- Voice direction tracking (DOA)
- Loudspeaker frequency response: 75 Hz–20 kHz
- 0.75-inch tweeter + 2-inch music driver
- Noise and echo cancellation
- Full-duplex audio
- Bluetooth 5.3 wireless connection to smartphones and PCs
- USB Type-C port for charging and wired PC connection
- USB dongle for PC connection
- Controls: buttons and LED indicators
- Bluetooth 5.3 (A2DP, AVRCP, HFP, HSP, and BLE)
- Linking: wireless connection of two MAXHUB BM31 units
- Dual Bluetooth: two sources can be used at once
- NFC for quick mobile-device connection
- Microphone frequency response: USB 100 Hz–15 kHz; Bluetooth 100 Hz–7.5 kHz
- Video conferencing software support
- Support for Mindlinker, Tencent Meeting, Microsoft Teams, Zoom, and others
Every feature points to a top-class speakerphone with improved sound. It has an array of 8 microphones, a two-way loudspeaker system, and advanced electronics. Along with AI noise and echo cancellation, it tracks the speaker's direction through DOA, or Direction-of-Arrival.
| BM21 | BM31 | BM41 | |
|---|---|---|---|
| Voice pickup range | 5 meters | 6 meters | 6 meters |
| Microphone | 6-element microphone array | 8-element microphone array | 8-element microphone array |
| Frequency range | 150 Hz–8 kHz | 100 Hz–15 kHz | 100 Hz–15 kHz |
| Loudspeaker | |||
| Sound pressure level | Full-range driver | 0.75-inch tweeter, 1.75-inch driver | 0.75-inch tweeter, 1.75-inch driver |
| Operating frequency range | 150 Hz–16 kHz | 75 Hz–20 kHz | 75 Hz–20 kHz |
| Inputs, outputs, buttons, indicators | |||
| Inputs/outputs | USB Type C 3.5 mm AUX (audio input/output) |
USB Type C | USB Type C |
| Linking multiple units | Yes, with an optional cable | Yes, wireless TWS mode | Yes, wireless TWS mode |
| Bluetooth | Version 4.2 + EDR | Version 5.3 | Version 5.3 |
| Buttons | Power, Answer/End, Microphone mute, Bluetooth, Volume+, Volume- | Power, Answer/End, Microphone mute, Bluetooth, Volume+, Volume- | Power, Answer/End, Microphone mute, Bluetooth, Volume+, Volume- |
| Indicators | Power, Volume, Bluetooth, Microphone, Answer/End | Power, Volume, Bluetooth, Microphone, TWS | Power, Volume, Bluetooth, Microphone, TWS |
| Physical specifications | |||
| Dimensions | 120 mm × 35 mm | 127 mm × 35 mm | 127 mm × 35 mm |
| Weight | 380 g | 470 g | 380 g |
| Color | Dark gray | Dark gray | Dark gray |
| Battery | |||
| Capacity | 7.4 V/2200 mAh | 3.7 V/4400 mAh | 3.7 V/4400 mAh |
| Charging requirements | Wired charging, 5 V/2 A | Wired charging, 5 V/1 A | Wired charging, 5 V/1 A |
| Operating time | Up to 8 hours | Up to 8 hours of music, 15 hours of calls | Up to 8 hours, 15 hours of calls |
The comparison table shows that the BM31 is a class above the BM21 and gives up nothing to the BM41. We can conclude that the main difference from the BM41 is appearance. The BM31 looks like a classic high-tech office speakerphone, while the BM41 resembles a smart speaker with fabric over its drivers. More details about that model are in a separate review.
The speakerphone comes in a premium embossed designer box. Everything emphasizes the product's high-end position.
Inside, a foam-polymer insert holds the speakerphone and all necessary accessories.
A small Russian manual is printed on glossy coated paper. The speakerphone is easy to use, however. Anyone familiar with similar devices will understand it without instructions. A useful function is battery indication. A short press of the power button makes the segmented LED ring around the loudspeaker show battery charge. Hold Power to switch on or off, preventing accidental operation.
The manual's last page explains wireless linking. Simply place two speakerphones next to each other and double-press each Bluetooth button in turn.
Everything necessary is included. A separate compartment holds a 5 V/1 A mains adapter, a PC/charging cable, and a USB wireless dongle. In our view, the dongle ensures that the speakerphone always works in its intended Bluetooth 5.3 mode.
Build quality is excellent. The all-metal housing, 470 g weight, and rubber underside keep the speakerphone from moving across the desk. Button presses cause no creaks or looseness. The small 127 × 35 mm dimensions also make business travel practical.
The built-in two-way loudspeaker covers the full frequency range with natural tone. It can reproduce voices during calls and serve as a powered speaker for video playback. This is useful in education, for example. We watched several YouTube teaching videos and were pleased. Speech clarity and clean volume are far better than the built-in speakers of a laptop or smartphone.
Eight microphones, two on each side, pick up speech reliably from every direction. DSP provides familiar functions: acoustic echo cancellation (AEC), automatic gain control (AGC), and noise cancellation (ANC). It also provides advanced direction tracking through DOA. The speakerphone follows the presenter's voice as the person moves around. As usual, we tested it in a 5-by-6-meter meeting room. We had no problems and did not need to raise our voices. The person at the other end was comfortable too.
As usual for Maxhub, touch buttons provide most functions. A loudspeaker sound confirms each touch, making operation straightforward. The segmented ring shows volume when + or - is pressed. The crossed-out microphone button temporarily mutes speech, for example to cough or drink water. This is useful in air-conditioned rooms. Everything is simple and convenient. Button illumination is helpful in darkened rooms.
USB-C allows the battery to charge while the speakerphone works through a wired USB connection to a PC. This helps when the battery is nearly empty. Wireless operation uses standard Bluetooth or the branded USB dongle.
The speakerphone is detected immediately and works in applications from Teams to Skype. Here is the Microsoft Teams settings panel:
The speakerphone already provides hardware processing, so software processing should be disabled to avoid processing voice twice and causing distortion. We did this. A test call before a meeting can show how the voice sounds at the other end. Voice transmission and remote speech playback are excellent and comfortable, allowing full attention to the business discussion.
To add a second Maxhub BM31, double-press the Bluetooth symbol. The speakerphones then work as a pair, expanding coverage and increasing playback volume. This allows use in a larger meeting room. Controls are linked and work from either unit.
Conclusions
The Maxhub BM31 left a very positive impression. It is a genuinely premium HD speakerphone that meets modern requirements. Its high-tech design fits any office, while 8 microphones and a two-way loudspeaker provide excellent sound. Built-in processing is useful in difficult conditions, such as window noise or a presenter walking around. Wired and wireless connections are supported by a USB dongle for compatibility with different devices and operating systems. Linking two units makes the BM31 attractive for both small and medium-sized meeting rooms. Add up to 15 hours of battery operation, and this is a true flagship suitable for the offices of leading companies.
If these capabilities are more than needed, consider the more affordable model, the Maxhub BM21.
Note. This is an adapted machine translation into English. It follows the “In simple terms” approach. Read the original article at https://prosound.ixbt.com/microphones/maxhub-bm31.shtml.