Short answer: the Brane X. It ranks #4 of 115 large speakers by sound quality, rated 4.6/5, at $549. The Marshall Kilburn II ranks #43, rated 3.8/5, at $219, $330 cheaper, not enough of a saving to outweigh the sound-quality gap.
The Marshall Kilburn II is the longer-running, lighter choice. A rugged Marshall styled stereo speaker with a leather handle, quick charging and a sound that suits rock. It is rated for 20 hours of battery against 12 for the Brane X. At 5.5 lbs (2.49 kg) it weighs noticeably less than the Brane X at 7.7 lbs (3.5 kg). The catch: Boosted upper bass, not very detailed, not as deep bass as competitors, upper mids peak.
The Brane X is the better-sounding, deeper-bass option. A portable speaker with extraordinarily deep bass for its size, plus Wi-Fi, AirPlay, Alexa and a low latency aux input. Its bass reaches about 31Hz before falling 10dB, against 58Hz for the Marshall Kilburn II. It is rated IP57 against IPX2 for the Marshall Kilburn II. It supports aptX HD Bluetooth, which the Marshall Kilburn II lacks. Watch for: The front-facing design has only moderate dispersion, so sound changes noticeably off to the sides or behind it.
Buy the Brane X. It is rated higher for sound quality, and the $330 you would save on the Marshall Kilburn II does not close the gap.
Want more options? Browse the full Portable Bluetooth rankings.
A rugged Marshall styled stereo speaker with a leather handle, quick charging and a sound that suits rock.
A portable speaker with extraordinarily deep bass for its size, plus Wi-Fi, AirPlay, Alexa and a low latency aux input.
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Specifications Side By Side
| Marshall Kilburn II | Brane X | |
|---|---|---|
| Price | $219.00 | $549.00 |
| Ranked | #43 of 115 in Large Size Portable Bluetooth Speakers | #4 of 115 in Large Size Portable Bluetooth Speakers |
| Aux Input | Yes | Yes |
| Bass Extension (-10dB) | ~58Hz | 31Hz |
| Battery Life | 20 hours (Manufacturer specified) | 12 hours (Manufacturer specified) |
| IP Rating | IPX2 | IP57 |
| Weight | 5.5 lbs (2.49 kg) | 7.7 lbs (3.5 kg) |
| App | No | Yes (Brane app) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | aptX HD, aptX, AAC, SBC |
| Built-in Microphone | Yes | Yes |
| EQ | No | Yes (5 band) |
| Party Mode | No | Yes (Brane app, up to 8 speakers) |
| Power Bank | No | No |
| Power Input | USB-C | AC Power brick |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Amplifier Power | 36W | 200W |
| Dimensions | 9.6” x 6.4” x 5.5” (243 x 162 x 140 mm) | 9.3” x 7” x 6.1” (236 x 178 x 155 mm) |
| Drivers | 1x 4” (102mm) woofer + 2x 20mm dome tweeters | 2x 2.5” midrange, 2x 0.75” tweeters + 6.5”x9” subwoofer |
| Maximum SPL | 102dB (Manufacturer specified) | 106dB (measured by Alan Ross Reviews) |
| Digital Aux Input | No | No |
| Bluetooth Version | 5.0 | 5.1 |
| Strap | Yes (built-in strap) | No |
| Aux Latency | - | 295ms default, 33ms with aux pass-through |
| Bluetooth Latency | - | 100ms |
| Wi-Fi | - | Yes |
| Voice Assistants | - | Amazon Alexa |
| Frequency Response | - | 30Hz - 20kHz (Manufacturer specified) |
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