Short answer: the Marshall Stockwell III on measured sound quality, the Ultimate Ears Epicboom on price. The Marshall Stockwell III ranks #56 of 78 large speakers at $249.99. The Ultimate Ears Epicboom ranks #58 at $213.41, $36.58 cheaper.
What the Marshall Stockwell III offers: 40+ hour battery life with a user-replaceable battery, strap, sleeve and grilles. Doubles as a USB-C power bank. IP55 dust/water resistance. App includes parametric EQ, a Soundstage widening control, and wall/corner placement compensation. Endless-rotation control knobs. Watch for: Highs are recessed by default and need the treble control maxed to compensate, still lacking detail even then. Bass tends to sound resonant and boomy, with reported frequency cancellation and phase issues on complex material that EQ doesn’t fully resolve. Oluv’s A/B testing against the outgoing Stockwell 2 finds the default tuning muffled and muddy enough to prefer the seven-year-old original out of the box, and output loses dynamics and bass while turning harsh well below maximum volume. No aptX support.
What the Ultimate Ears Epicboom offers: 17 hour battery with USB-C charging (first UE portable with USB-C). IP67 rating, floats in water. Made mostly from recycled fabric and plastic. Large best-sounding UE portable that still feels portable. 180ft Bluetooth range. Watch for: Not very deep bass for the size. Gets distorted at around 70-80% with bass thuds.
Buy the Marshall Stockwell III when sound quality outweighs the price for you, and the Ultimate Ears Epicboom when the price outweighs sound quality instead.
Battery life favors the Marshall Stockwell III: rated for 40 hours against 17 hours for the Ultimate Ears Epicboom.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Marshall Stockwell III | Ultimate Ears Epicboom | |
|---|---|---|
| Price | $249.99 | $213.41 |
| Ranked | #56 of 78 in Large Size Portable Bluetooth Speakers | #58 of 78 in Large Size Portable Bluetooth Speakers |
| Drivers | 1x 3" woofer, 2x 1.75" wide-band drivers | 1x 120mm woofer, 2x 45mm tweeters |
| Frequency Response | 54Hz - 20kHz (Manufacturer specified) | 50Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | 44W | 10W RMS |
| Battery Life | 40+ hours (Manufacturer specified) | 17 hours (Manufacturer specified) |
| Bluetooth Version | 5.3 | 5.2 |
| Bluetooth Codecs | SBC, AAC, LE Audio with LC3 | SBC |
| IP Rating | IP55 | IPX7 |
| Weight | 2.9 lbs (1.3 kg) | 4.3 lbs (1.97 kg) |
| Dimensions | 7.1" x 6.4" x 2.9" (180 x 162 x 74 mm) | 4.7" x 9.5" x 6.4" (119 x 241 x 162 mm) |
| App | Yes | No |
| EQ | Yes (parametric, via app) | No |
| Aux Input | Yes | Yes |
| Digital Aux Input | No | No |
| Power Bank | Yes | No |
| Power Input | USB-C | USB-C |
| Stereo | Partially | Yes |
| Omnidirectional | Yes | No |
| Bass Extension (-10dB) | - | ~55Hz |
| Built-in Microphone | - | Yes |
| Party Mode | - | No |
| TWS | - | Yes |
| Maximum SPL | - | 94dB (Manufacturer specified) |
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Prices on this page were last checked September 16, 2026 at 12:41 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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The Two Speakers In Full
Marshall Stockwell III: $249.99 Marshall eBay
Pros: 40+ hour battery life with a user-replaceable battery, strap, sleeve and grilles. Doubles as a USB-C power bank. IP55 dust/water resistance. App includes parametric EQ, a Soundstage widening control, and wall/corner placement compensation. Endless-rotation control knobs.
Cons: Highs are recessed by default and need the treble control maxed to compensate, still lacking detail even then. Bass tends to sound resonant and boomy, with reported frequency cancellation and phase issues on complex material that EQ doesn’t fully resolve. Oluv’s A/B testing against the outgoing Stockwell 2 finds the default tuning muffled and muddy enough to prefer the seven-year-old original out of the box, and output loses dynamics and bass while turning harsh well below maximum volume. No aptX support.
Full Marshall Stockwell III review and specifications →
| Amplifier Power | 44W |
|---|---|
| App | Yes |
| Aux Input | Yes |
| Battery Life | 40+ hours (Manufacturer specified) |
| Bluetooth Codecs | SBC, AAC, LE Audio with LC3 |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 7.1" x 6.4" x 2.9" (180 x 162 x 74 mm) |
| Drivers | 1x 3" woofer, 2x 1.75" wide-band drivers |
| EQ | Yes (parametric, via app) |
| Frequency Response | 54Hz - 20kHz (Manufacturer specified) |
| IP Rating | IP55 |
| Omnidirectional | Yes |
| Power Bank | Yes |
| Power Input | USB-C |
| Stereo | Partially |
| Weight | 2.9 lbs (1.3 kg) |
- Links
- Reviews, Comparisons and Sound Samples
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Ultimate Ears Epicboom: $213.41 Amazon eBay
Pros: 17 hour battery with USB-C charging (first UE portable with USB-C). IP67 rating, floats in water. Made mostly from recycled fabric and plastic. Large best-sounding UE portable that still feels portable. 180ft Bluetooth range. Measured bass extension of ~55Hz (-10dB).
Cons: Not very deep bass for the size. Gets distorted at around 70-80% with bass thuds.
Full Ultimate Ears Epicboom review and specifications →
| Amplifier Power | 10W RMS |
|---|---|
| App | No |
| Aux Input | Yes |
| Bass Extension (-10dB) | ~55Hz |
| Battery Life | 17 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 4.7" x 9.5" x 6.4" (119 x 241 x 162 mm) |
| Drivers | 1x 120mm woofer, 2x 45mm tweeters |
| EQ | No |
| Frequency Response | 50Hz - 20kHz (Manufacturer specified) |
| IP Rating | IPX7 |
| Maximum SPL | 94dB (Manufacturer specified) |
| Omnidirectional | No |
| Party Mode | No |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| Weight | 4.3 lbs (1.97 kg) |
- Links
- Reviews, Comparisons and Sound Samples
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