Short answer: the JBL Xtreme 3. It ranks #18 of 115 large speakers by sound quality, rated 4.3/5, at $269.95. The Marshall Stockwell III ranks #79, rated 3.0/5, at $249.99, $19.96 cheaper, a saving that is not big enough to make up the sound-quality gap.
The JBL Xtreme 3 is the better-sounding, tougher pick. A loud, waterproof stereo speaker with deep bass, balanced sound and a power bank for charging devices. It is rated IPX7 against IP55 for the Marshall Stockwell III. The catch: Boosted bass.
The Marshall Stockwell III is the longer-running, lighter choice. A stylish, rugged speaker with a very long battery you can swap yourself, a detailed app EQ, and power bank charging. It is rated for 40 hours of battery against 15 for the JBL Xtreme 3. At 2.9 lbs (1.3 kg) it weighs noticeably less than the JBL Xtreme 3 at 4 lbs (1.83 kg). It supports AAC Bluetooth, which the JBL Xtreme 3 lacks. The tradeoff: Highs are recessed by default and need the treble control maxed to compensate, still lacking detail even then.
Buy the JBL Xtreme 3. It is rated higher for sound quality, and the $19.96 saving on the Marshall Stockwell III is not enough to make up the difference.
Want more options? Browse the full Portable Bluetooth rankings.
A loud, waterproof stereo speaker with deep bass, balanced sound and a power bank for charging devices.
A stylish, rugged speaker with a very long battery you can swap yourself, a detailed app EQ, and power bank charging.
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
| JBL Xtreme 3 | Marshall Stockwell III | |
|---|---|---|
| Price | $269.95 | $249.99 |
| Ranked | #18 of 115 in Large Size Portable Bluetooth Speakers | #79 of 115 in Large Size Portable Bluetooth Speakers |
| Aux Input | Yes | Yes |
| Bass Extension (-10dB) | 53Hz | - |
| Battery Life | 15 hours (Manufacturer specified) | 40+ hours (Manufacturer specified) |
| Bluetooth Latency | 133ms | - |
| Maximum SPL | 105dB (measured by Alan Ross Reviews) | - |
| Party Mode | Yes (PartyBoost up to 100 speakers) | - |
| Power Bank | Yes (USB-A + USB-C) | Yes |
| Power Input | USB-C | USB-C |
| Stereo | Yes | Partially |
| Omnidirectional | No | Yes |
| TWS | Yes | No |
| Weight | 4 lbs (1.83 kg) | 2.9 lbs (1.3 kg) |
| App | No | Yes |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC, AAC, LE Audio with LC3 |
| Built-in Microphone | Yes | - |
| EQ | No | Yes (parametric, via app) |
| IP Rating | IPX7 | IP55 |
| Bluetooth Version | 4.1 | 5.3 |
| Dimensions | 11.7” x 5.4” x 5.3” (298 x 136 x 134 mm) | 7.1” x 6.4” x 2.9” (180 x 162 x 74 mm) |
| Drivers | 2x 70mm woofers, 2x 20mm tweeters | 1x 3” woofer, 2x 1.75” wide-band drivers |
| Frequency Response | 53.5Hz - 20kHz (Manufacturer specified) | 54Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | 100W | 44W |
| Digital Aux Input | No | No |
| Strap | Yes (detachable shoulder strap) | Yes (detachable strap) |
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