Short answer: the Zealot S79. It ranks #52 of 126 large speakers by sound quality, rated 3.6/5, at $106.97; the Sony ULT Field 5 ranks #59, rated 3.5/5, and costs $348, so there is little reason to consider the other one.
The Zealot S79 is the longer-running option. A loud party speaker with plenty of bass, a huge battery that doubles as a power bank, lights and a shoulder strap. It is rated for 50 hours of battery against 25 for the Sony ULT Field 5. The tradeoff: At moderate volume the JBL Xtreme 3 is cleaner and more balanced, and one reviewer preferred the JBL Xtreme 4 in every way.
Why pick the Sony ULT Field 5: A tough, waterproof party speaker with loud, bass focused output, an aux input, a power bank and a long battery. The tradeoff: It prioritizes bass and loudness over fidelity: reviews find the upper mids and highs subdued, with limited stereo separation and soundstage depth.
Buy the Zealot S79. 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.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Prices on this page were last checked November 14, 2026 at 6:17 PM 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
| Zealot S79 | Sony ULT Field 5 | |
|---|---|---|
| Price | $106.97 | $348.00 |
| Ranked | #52 of 126 in Large Size Portable Bluetooth Speakers | #59 of 126 in Large Size Portable Bluetooth Speakers |
| Amplifier Power | 100W (150W peak) | 27W |
| Drivers | 2 woofers + 2 tweeters | 2x 46mm tweeters + 1x 79mm x 107mm woofer |
| Battery Life | 50+ hours (Manufacturer specified) | 25 hours (Manufacturer specified) |
| Power Bank | Yes | Yes (USB-C) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 5.3 |
| TWS | Yes | Yes |
| Lights | Yes | - |
| Weight | 7.3 lbs (3.3 kg) | 7.3 lbs (3.3 kg) |
| Dimensions | 13.4” x 7.2” x 5.7” (340 x 184 x 146 mm) | 12.6” x 5.7” x 4.9” (320 x 144 x 125 mm) |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| Strap | Yes (detachable shoulder strap) | Yes (detachable shoulder strap) |
| IP Rating | IPX6 | IP67 |
| App | - | Yes |
| Aux Input | - | Yes |
| Bluetooth Codecs | - | SBC, AAC, LDAC |
| Built-in Microphone | - | Yes |
| EQ | - | Yes (App + ULT button) |
| Party Mode | - | Yes (Party Connect up to 100 speakers) |
| Power Input | - | USB-C |
| Digital Aux Input | - | No |
Where the Ratings Come From
- Zealot S79: reviews by Jagist, YARNZO Tech and flmclau.
- Sony ULT Field 5: reviews by Joy & Oluv’Sone, Dominik and Mateusz Cholewa.
This comparison is generated from the ratings, specifications and measurements on each product’s own page, and it updates when that data changes. How we rank explains how each rating is decided.
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