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 Sony ULT Field 5 ranks #56, rated 3.5/5, and costs $268, so there is not much of a tradeoff to weigh.
The Sony ULT Field 5 is the longer-running pick. A tough, waterproof party speaker with loud, bass focused output, an aux input, a power bank and a long battery. It is rated for 25 hours of battery against 16 for the Onn Portable FM Boombox. It has an adjustable EQ, which the Onn Portable FM Boombox lacks. The catch: It prioritizes bass and loudness over fidelity: reviews find the upper mids and highs subdued, with limited stereo separation and soundstage depth.
The Onn Portable FM Boombox is the better-sounding, lighter choice. An excellent value waterproof boombox that floats, with reasonably deep bass, FM radio, lights and a long battery. At 4.9 lbs (2.22 kg) it weighs noticeably less than the Sony ULT Field 5 at 7.3 lbs (3.3 kg). 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 Sony ULT Field 5 and costs less, which makes it the one to get unless you need something the other one does better.
Want more options? Browse the full Portable Bluetooth rankings.
A tough, waterproof party speaker with loud, bass focused output, an aux input, a power bank and a long battery.
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
| Sony ULT Field 5 | Onn Portable FM Boombox | |
|---|---|---|
| Price | $268.00 | $74.83 |
| Ranked | #56 of 115 in Large Size Portable Bluetooth Speakers | #26 of 115 in Large Size Portable Bluetooth Speakers |
| App | Yes | No |
| Aux Input | Yes | Yes |
| Battery Life | 25 hours (Manufacturer specified) | 16 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, AAC, LDAC | SBC (inferred; additional codecs unverified) |
| Bluetooth Version | 5.3 | - |
| Built-in Microphone | Yes | Yes |
| Dimensions | 12.6” x 5.7” x 4.9” (320 x 144 x 125 mm) | 13.8” x 5.9” x 7.7” (350 x 149 x 195 mm) |
| Drivers | 2x 46mm tweeters + 1x 79mm x 107mm woofer | 2 speakers |
| EQ | Yes (App + ULT button) | No |
| IP Rating | IP67 | IPX7 |
| Party Mode | Yes (Party Connect up to 100 speakers) | Yes (Party Sync, pairs with 1 other onn. speaker) |
| Power Bank | Yes (USB-C) | Yes (USB-A) |
| Power Input | USB-C | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 7.3 lbs (3.3 kg) | 4.9 lbs (2.22 kg) |
| Amplifier Power | 27W | 25W RMS (100W peak) |
| Digital Aux Input | No | No |
| Strap | Yes (detachable shoulder strap) | - |
| FM Tuner | - | Yes (10 presets) |
| Removable Battery | - | No |
| Lights | - | Yes |
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