Short answer: the Boombox 4 for raw output, the ULT Field 7 for a lower price and more inputs. The Boombox 4 ranks #20 of 113 boombox speakers against the ULT Field 7’s #61, and costs $101.95 more.
The Boombox 4’s strength is sheer output, not out-of-the-box tuning. Its pros call out pretty insane output capability for the size, backed by 210W of AC power and a 41Hz bass extension. But its own cons note it is pretty overpriced for the category, and that most of its gain over the Boombox 3 comes from having 7 EQ bands instead of 3 rather than a real tuning upgrade. Out of the box, it reportedly sounds worse than the Boombox 3, so getting the best from it means dialing in a custom EQ.
The ULT Field 7 is a step up from Sony’s own lineup but still trails the class leaders. Its pros note it sounds better than Sony’s own XG500, but the cons are direct: still not as deep in the bass as the top ranked speakers, plus a peak around 8kHz. Its bass extension measures around 52Hz against the Boombox 4’s 41Hz.
What the ULT Field 7 has that the Boombox 4 does not:
- A 3.5mm aux input, which the Boombox 4 dropped entirely.
- A built-in microphone with karaoke mode and a guitar input.
- USB playback and LDAC codec support, versus the Boombox 4’s LC3.
What the Boombox 4 has that the ULT Field 7 does not: a removable battery, IP68 rating versus IP67, and a USB-C power bank output rated up to 30W.
Buy the Boombox 4 if maximum output and a removable battery matter most, and you are willing to spend time in the EQ to get it sounding right.
Buy the ULT Field 7 if you want a lower price, an aux input for wired sources, and karaoke-ready mic and guitar inputs, and can live with less bass depth and a treble peak.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Prices on this page were last checked November 11, 2026 at 3:26 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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Specifications Side By Side
| JBL Boombox 4 | Sony ULT Field 7 | |
|---|---|---|
| Price | $549.95 | $448.00 |
| Ranked | #20 of 113 in Boombox Size Portable Bluetooth Speakers | #61 of 113 in Boombox Size Portable Bluetooth Speakers |
| App | Yes | No |
| Aux Input | No | Yes |
| Bass Extension (-10dB) | 41Hz | ~52Hz |
| Battery Life | 28 hours (Manufacturer specified) | 30 hours (Manufacturer specified) |
| EQ | Yes (7 band) | Yes (App + ULT button) |
| IP Rating | IP68 | IP67 |
| Bluetooth Latency | AAC 144ms, SBC 48ms | - |
| Maximum SPL | 115dB (measured by Alan Ross Reviews) | - |
| Party Mode | Yes (Auracast) | Yes (Party Connect up to 100 speakers) |
| Power Input | AC Power cord | AC Power cord |
| Removable Battery | Yes | - |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| Weight | 13.2 lbs (5.98 kg) | 13.9 lbs (6.3 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, LC3, AAC | SBC, AAC, LDAC |
| Bluetooth Version | 5.4 | 5.2 |
| Built-in Microphone | No | Yes |
| Power Bank | Yes (USB-C, up to 30W) | Yes (USB-A, 5V/1.5A) |
| TWS | Yes | Yes |
| Digital Aux Input | Yes (USB-C) | No |
| USB Playback | No | Yes |
| FM Tuner | No | - |
| Microphone Input | No | Yes (Karaoke mode with echo effect) |
| MicroSD Playback | No | - |
| Amplifier Power | 210W AC / 200W battery | 100W |
| Dimensions | 20.1” x 10.2” x 8.3” (510 x 260 x 210 mm) | 20.2” x 8.8” x 8.7” (512 x 224 x 222 mm) |
| Drivers | 2x 123mm woofers + 2x 20mm tweeters with passive radiators | 2x 114mm x 114mm X-Balanced woofers + 2x 46mm (1.9”) tweeters |
| Strap | No | No |
| Guitar Input | - | Yes |
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