Short answer: the Onn Portable FM Boombox. It ranks #26 of 115 large speakers by sound quality, rated 4.2/5, at $74.83; the Marshall Kilburn II ranks #43, rated 3.8/5, and costs $219, so there is little reason to consider the other one.
Why pick the Marshall Kilburn II: A rugged Marshall styled stereo speaker with a leather handle, quick charging and a sound that suits rock. The catch: Boosted upper bass, not very detailed, not as deep bass as competitors, upper mids peak.
The Onn Portable FM Boombox is the better-sounding, tougher choice. An excellent value waterproof boombox that floats, with reasonably deep bass, FM radio, lights and a long battery. It is rated IPX7 against IPX2 for the Marshall Kilburn II. It links with other speakers (Party Sync, pairs with 1 other onn. speaker), which the Marshall Kilburn II cannot. Watch for: Reasonable frequency response, but not quite as smooth as some of the top-ranked speakers in this size.
Buy the Onn Portable FM Boombox. It is rated higher for sound quality than the Marshall Kilburn II and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Looking for alternatives? See the complete Portable Bluetooth rankings.
A rugged Marshall styled stereo speaker with a leather handle, quick charging and a sound that suits rock.
An excellent value waterproof boombox that floats, with reasonably deep bass, FM radio, lights and a long battery.
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Specifications Side By Side
| Marshall Kilburn II | Onn Portable FM Boombox | |
|---|---|---|
| Price | $219.00 | $74.83 |
| Ranked | #43 of 115 in Large Size Portable Bluetooth Speakers | #26 of 115 in Large Size Portable Bluetooth Speakers |
| Aux Input | Yes | Yes |
| Bass Extension (-10dB) | ~58Hz | - |
| Battery Life | 20 hours (Manufacturer specified) | 16 hours (Manufacturer specified) |
| IP Rating | IPX2 | IPX7 |
| Weight | 5.5 lbs (2.49 kg) | 4.9 lbs (2.22 kg) |
| App | No | No |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC (inferred; additional codecs unverified) |
| Built-in Microphone | Yes | Yes |
| EQ | No | No |
| Party Mode | No | Yes (Party Sync, pairs with 1 other onn. speaker) |
| Power Bank | No | Yes (USB-A) |
| Power Input | USB-C | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Amplifier Power | 36W | 25W RMS (100W peak) |
| Dimensions | 9.6” x 6.4” x 5.5” (243 x 162 x 140 mm) | 13.8” x 5.9” x 7.7” (350 x 149 x 195 mm) |
| Drivers | 1x 4” (102mm) woofer + 2x 20mm dome tweeters | 2 speakers |
| Maximum SPL | 102dB (Manufacturer specified) | - |
| Digital Aux Input | No | No |
| Bluetooth Version | 5.0 | - |
| Strap | Yes (built-in strap) | - |
| FM Tuner | - | Yes (10 presets) |
| Removable Battery | - | No |
| Lights | - | Yes |
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