Short answer: the Xiaomi Sound Outdoor. It ranks #46 of 177 medium speakers by sound quality, rated 3.7/5, at $49.99; the Ultimate Ears Wonderboom 4 ranks #108, rated 2.9/5, and costs $64.99, which makes this an easy call rather than a real tradeoff.
The Ultimate Ears Wonderboom 4 is the lighter choice. A small, tough waterproof speaker with a strap loop and USB-C charging, easy to clip on a bag for outdoor trips. At 0.9 lbs (420 g) it weighs noticeably less than the Xiaomi Sound Outdoor at 1.3 lbs (597 g). The catch: Bass isn’t as deep as the top-ranked speakers and is a little thuddy.
The Xiaomi Sound Outdoor is the better-sounding option. An affordable waterproof outdoor speaker with a separate tweeter, decent battery life and linking to many more speakers. It links with other speakers (Speakersync, up to 100 speakers), which the Ultimate Ears Wonderboom 4 cannot. Watch for: Bass reach is limited for the cabinet size, with a rated lower limit of 60Hz, and the boosted bass gets somewhat uncontrolled at high levels.
Buy the Xiaomi Sound Outdoor. It is rated higher for sound quality than the Ultimate Ears Wonderboom 4 and costs less, so only choose the other one for a particular feature it does better.
Looking for alternatives? See the complete Portable Bluetooth rankings.
A small, tough waterproof speaker with a strap loop and USB-C charging, easy to clip on a bag for outdoor trips.
An affordable waterproof outdoor speaker with a separate tweeter, decent battery life and linking to many more speakers.
Prices on this page were last checked October 31, 2026 at 7:11 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.
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Specifications Side By Side
| Ultimate Ears Wonderboom 4 | Xiaomi Sound Outdoor | |
|---|---|---|
| Price | $64.99 | $49.99 |
| Ranked | #108 of 177 in Medium Size Portable Bluetooth Speakers | #46 of 177 in Medium Size Portable Bluetooth Speakers |
| Battery Life | 14 hours (Manufacturer specified) | 12 hours (Manufacturer specified) |
| Maximum SPL | 87dB (Manufacturer specified) | - |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Omnidirectional | Yes | No |
| Weight | 0.9 lbs (420 g) | 1.3 lbs (597 g) |
| IP Rating | IP67 | IP67 |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.2 | 5.4 |
| Dimensions | 4.1” x 3.8” (104 x 95.3 mm) | 7.7” x 2.7” x 2.6” (196.6 x 68 x 66 mm) |
| Drivers | 2x 40mm active drivers + 2x passive radiators (46.1 x 65.2mm) | 20W woofer, 10W tweeter + 2x passive radiators |
| TWS | Yes | Yes |
| Party Mode | No | Yes (Speakersync, up to 100 speakers) |
| App | No | No |
| EQ | No | No |
| Built-in Microphone | No | Yes |
| Power Bank | No | - |
| Aux Input | No | No |
| Digital Aux Input | No | No |
| Bluetooth Codecs | SBC | SBC (inferred; additional codecs unverified) |
| Strap | Yes (built-in loop) | - |
| Frequency Response | - | 60Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | - | 30W |
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