These are not really the same size class, and that is the honest framing here. The Soundcore Boom Go 3i ranks #2 of 62 small speakers by sound quality at $59.98; the Ultimate Ears Wonderboom 4 ranks #109 of 179 medium speakers by sound quality at $64.99.
The Soundcore Boom Go 3i is the longer-running option. A tough, floating mini speaker with full waterproofing, a long battery and a detachable strap, built for travel and the outdoors. It is rated for 24 hours of battery against 14 for the Ultimate Ears Wonderboom 4. It links with other speakers (Auracast), which the Ultimate Ears Wonderboom 4 cannot. It has an adjustable EQ, which the Ultimate Ears Wonderboom 4 lacks. The catch: This is still a 15W mono speaker: bass impact and stereo width are limited, and critical listeners may find the upper treble piercing or metallic.
Why pick the Ultimate Ears Wonderboom 4: A small, tough waterproof speaker with a strap loop and USB-C charging, easy to clip on a bag for outdoor trips. Watch for: Bass isn’t as deep as the top-ranked speakers and is a little thuddy.
Buy the Soundcore Boom Go 3i ($59.98) for a small speaker; the Ultimate Ears Wonderboom 4 ($64.99) suits a medium speaker instead.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Prices on this page were last checked November 11, 2026 at 3:26 AM 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
| Soundcore Boom Go 3i | Ultimate Ears Wonderboom 4 | |
|---|---|---|
| Price | $59.98 | $64.99 |
| Ranked | #2 of 62 in Small Size Portable Bluetooth Speakers | #109 of 179 in Medium Size Portable Bluetooth Speakers |
| App | Yes | No |
| Aux Input | No | No |
| Battery Life | 24 hours (Manufacturer specified) | 14 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| Built-in Microphone | Yes | No |
| EQ | Yes | No |
| IP Rating | IP68 | IP67 |
| Party Mode | Yes (Auracast) | No |
| Power Bank | Yes (USB-C) | No |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Omnidirectional | Pointing up | Yes |
| TWS | Yes | Yes |
| Weight | 0.8 lbs (380 g) | 0.9 lbs (420 g) |
| Bluetooth Version | 6.0 | 5.2 |
| Amplifier Power | 15W | - |
| Dimensions | 4” x 4.2” x 1.8” (102.1 x 105.9 x 45.5 mm) | 4.1” x 3.8” (104 x 95.3 mm) |
| Drivers | 25mm tweeter + 42mm woofer + passive radiators | 2x 40mm active drivers + 2x passive radiators (46.1 x 65.2mm) |
| Maximum SPL | 92dB (Manufacturer specified) | 87dB (Manufacturer specified) |
| Digital Aux Input | No | No |
| Lights | Yes | - |
| Strap | Yes (detachable strap) | Yes (built-in loop) |
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