Short answer: the Sony ULT Field 3, if you are buying new. The Bogasing M4 ranks higher than it (#28 vs #74 of 164 medium speakers, 4.0/5 vs 3.4/5) but is discontinued, so only consider it used; the Sony ULT Field 3 is still sold new at $208.
The Bogasing M4 is the better-sounding, lighter option. Super Bass mode gives the most balanced sound. At 1.6 lbs (731 g) it weighs much less than the Sony ULT Field 3 at 2.6 lbs (1.2 kg). It keeps a wired aux input, which the Sony ULT Field 3 lacks. The catch: It sounds a bit harsh and thin.
The case for the Sony ULT Field 3: IP67 rated, dustproof and water resistant. It has an adjustable EQ, which the Bogasing M4 lacks. The tradeoff: Sounds a bit hollow, a bit boosted in the treble.
Buy the Sony ULT Field 3, since the Bogasing M4 is discontinued and only worth hunting down used.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Bogasing M4 | Sony ULT Field 3 | |
|---|---|---|
| Price | $45.99 Discontinued | $208.00 |
| Ranked | #28 of 164 in Medium Size Portable Bluetooth Speakers | #74 of 164 in Medium Size Portable Bluetooth Speakers |
| App | No | Yes |
| Aux Input | Yes | No |
| Bass Extension (-10dB) | 54Hz | - |
| Battery Life | 24 hours (Manufacturer specified) | 24 hours (Manufacturer specified) |
| EQ | No | Yes (App + ULT button) |
| IP Rating | IPX7 | IP67 |
| Bluetooth Latency | 150ms | - |
| Maximum SPL | 99dB (measured by Alan Ross Reviews) | - |
| MicroSD Playback | Yes | - |
| Power Input | USB-C | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 1.6 lbs (731 g) | 2.6 lbs (1.2 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.0 | 5.2 |
| Amplifier Power | 40W | 27W |
| Drivers | 52mm speaker unit | 1x 20mm tweeter + 1x 86mm x 46mm woofer |
| Digital Aux Input | No | No |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) | SBC, AAC, LDAC |
| Dimensions | 3.1”H x 8.4”W x 2.5”D (80 x 214 x 63 mm) | 10.1” x 4.4” x 3.1” (256 x 113 x 79 mm) |
| Built-in Microphone | - | Yes |
| Party Mode | - | Yes (Party Connect up to 100 speakers) |
| Power Bank | - | Yes (USB-C, 5V/1.5A) |
| Strap | - | Yes (detachable shoulder strap) |
Related Speaker Comparisons
How Bogasing M4 compares with other leading options:
- Bogasing M4 vs Earfun Uboom L
- Bogasing M4 vs Soundcore Motion 300
- Bogasing M4 vs Soundcore Motion+
- Bogasing M4 vs Minirig 4
- B&O Beosound A1 2nd gen vs Bogasing M4
Prices on this page were last checked October 4, 2026 at 9:58 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
As an eBay Partner, we may be compensated if you make a purchase.
The Two Speakers In Full
Bogasing M4: $45.99 Discontinued eBay
Newer model: the Bogasing M5, ranked lower, rated 3.5/5.
Pros: Bogasing M4 uses 52mm speaker unit. Its 731 g, claimed 24 hours (Manufacturer specified) battery life, IPX7 protection, aux input, up to 99dB and stereo playback make it a practical option for its intended room or portable use. Super Bass mode gives the most balanced sound. Measured bass extension of 54Hz (-10dB).
Cons: Bass is limited by its 54Hz specification. There is no companion app. No EQ adjustment. It sounds a bit harsh and thin. Discontinued.
Full Bogasing M4 review and specifications →
| Amplifier Power | 40W |
|---|---|
| App | No |
| Aux Input | Yes |
| Bass Extension (-10dB) | 54Hz |
| Battery Life | 24 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) |
| Bluetooth Latency | 150ms |
| Bluetooth Version | 5.0 |
| Digital Aux Input | No |
| Dimensions | 3.1”H x 8.4”W x 2.5”D (80 x 214 x 63 mm) |
| Drivers | 52mm speaker unit |
| EQ | No |
| IP Rating | IPX7 |
| Maximum SPL | 99dB (measured by Alan Ross Reviews) |
| MicroSD Playback | Yes |
| Omnidirectional | No |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| Weight | 1.6 lbs (731 g) |
- Reviews, Comparisons and Sound Samples
- Alan Ross Reviews: Bogasing M4 Review - vs JBL Charge 5 & Motion Plus - a new contender? More from alanrossreviews →
- Alan Ross Reviews: Bose Soundlink Flex vs Soundcore Boost vs Bogasing M4 - cheap or Bose?
- Alan Ross Reviews: Bogasing M4 or Soundcore Boost or Maxsound Plus for $50 champion?? 🤷♀️
- Alan Ross Reviews: Tronsmart Element Force review vs Bogasing M4 - cheap speaker 🤑
- Head-to-Head Comparisons
Sony ULT Field 3: $208.00 Amazon eBay
Older models: the Sony XB33 (ranked lower, rated 3.4/5), the Sony SRS-XE300 (ranked lower, rated 2.8/5) and the Sony SRS-XB30 (ranked lower, rated 2.6/5).
Pros: IP67 rated, dustproof and water resistant. 24 hour battery life. App with 10-band EQ. Party Connect with up to 100 speakers. USB-C in/out for charging your phone.
Cons: Sounds a bit hollow, a bit boosted in the treble. Custom EQ and the ULT bass-boost button can’t be used together: turning on ULT disables the EQ. Bass is very weak with ULT off. Lost to the JBL Charge 6 in a side-by-side comparison despite being the larger speaker.
Full Sony ULT Field 3 review and specifications →
| Amplifier Power | 27W |
|---|---|
| App | Yes |
| Aux Input | No |
| Battery Life | 24 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, AAC, LDAC |
| Bluetooth Version | 5.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 10.1” x 4.4” x 3.1” (256 x 113 x 79 mm) |
| Drivers | 1x 20mm tweeter + 1x 86mm x 46mm woofer |
| EQ | Yes (App + ULT button) |
| IP Rating | IP67 |
| Omnidirectional | No |
| Party Mode | Yes (Party Connect up to 100 speakers) |
| Power Bank | Yes (USB-C, 5V/1.5A) |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | Yes (detachable shoulder strap) |
| TWS | Yes |
| Weight | 2.6 lbs (1.2 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Sony ULT Field 3 vs Bose Soundlink Mini
- Sony ULT Field 3 vs Xiaomi Mi Portable
- Sony ULT Field 3 vs Sony XB33
- Sony ULT Field 3 vs Bose Soundlink Mini 2
- Sony ULT Field 3 vs Bose Portable Smart Speaker
- Sony ULT Field 3 vs Beats Pill 2024
- Sony ULT Field 3 vs Soundcore 3
- Sony ULT Field 3 vs JBL Flip 5
- See all 142 comparisons