These sit in different size classes, so this is not a straight ranking comparison. The Marshall Stockwell II ranks #11 of 120 large speakers by sound quality at $229.99; the Ultimate Ears Boom 4 ranks #113 of 179 medium speakers by sound quality at $114.99.
The Marshall Stockwell II is the longer-running pick. A light, strap equipped speaker with some of the most natural sound around, even off to the side, and a long battery. It is rated for 20 hours of battery against 15 for the Ultimate Ears Boom 4. It keeps a wired aux input, which the Ultimate Ears Boom 4 lacks. The tradeoff: Not very loud, and the added DSP reverb may annoy purists.
The Ultimate Ears Boom 4 is the lighter, tougher pick. A tough waterproof speaker that floats, with USB-C charging, app EQ and pairing with other UE speakers. At 1.4 lbs (620 g) it weighs much less than the Marshall Stockwell II at 3.1 lbs (1.4 kg). It is rated IP67 against IPX4 for the Marshall Stockwell II. It has an adjustable EQ, which the Marshall Stockwell II lacks. The catch: Not much improvement over the old ones.
Buy the Marshall Stockwell II ($229.99) for a large speaker; the Ultimate Ears Boom 4 ($114.99) suits a medium speaker instead.
Want more options? Browse the full Portable Bluetooth rankings.
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Specifications Side By Side
| Marshall Stockwell II | Ultimate Ears Boom 4 | |
|---|---|---|
| Price | $229.99 | $114.99 |
| Ranked | #11 of 120 in Large Size Portable Bluetooth Speakers | #113 of 179 in Medium Size Portable Bluetooth Speakers |
| Aux Input | Yes | No |
| Bass Extension (-10dB) | 44Hz | - |
| Battery Life | 20 hours (Manufacturer specified) | 15 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| IP Rating | IPX4 | IP67 |
| Bluetooth Latency | 50ms | - |
| Maximum SPL | 96dB (measured by Alan Ross Reviews) | 85dBC (Manufacturer specified) |
| Party Mode | No | - |
| Power Input | USB-C | USB-C |
| Stereo | No | Yes |
| Omnidirectional | Yes | No |
| TWS | No | Yes |
| Weight | 3.1 lbs (1.4 kg) | 1.4 lbs (620 g) |
| App | No | Yes |
| Built-in Microphone | Yes | No |
| EQ | No | Yes (via app) |
| Power Bank | No | No |
| Bluetooth Version | 5.0 | 5.1 |
| Dimensions | 7.1” x 6.3” x 2.8” (180 x 161 x 70 mm) | 7.2” x 2.9” x 2.9” (184 x 73 x 73 mm) |
| Drivers | 3” woofer, 2x 2” fullrange tweeters | 2x 1.57” (40mm) active drivers + 2x 1.81” x 2.57” (46.1 x 65.2mm) passive radiators |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) | - |
| Amplifier Power | 20W | - |
| Digital Aux Input | No | No |
| Strap | Yes (built-in strap) | Yes (built-in loop) |
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