Short answer: the Minirig 4. It ranks #7 of 177 medium speakers by sound quality, rated 4.3/5, at $229.95. The Sony ULT Field 3 ranks #71, rated 3.4/5, at $208, $21.95 cheaper, not enough of a saving to outweigh the sound-quality gap.
The Sony ULT Field 3 is the tougher choice. A rugged waterproof stereo speaker with long battery life, a detailed app EQ, a shoulder strap and a phone charging port. It is rated IP67 against Splash resistant for the Minirig 4. It supports LDAC Bluetooth, which the Minirig 4 lacks. It plays in stereo from a single unit, unlike the Minirig 4. The catch: Sounds a bit hollow, a bit boosted in the treble.
The Minirig 4 is the better-sounding, lighter pick. A small, long lasting speaker that gets loud and can add a matching subwoofer, with a 30 hour battery. At 1.2 lbs (550 g) it weighs much less than the Sony ULT Field 3 at 2.6 lbs (1.2 kg). It keeps a wired aux input, which the Sony ULT Field 3 lacks. Watch for: Calls itself splash resistant and has no official water rating.
Buy the Minirig 4. It is rated higher for sound quality, and the $21.95 saving on the Sony ULT Field 3 is not enough to make up the difference.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
A rugged waterproof stereo speaker with long battery life, a detailed app EQ, a shoulder strap and a phone charging port.
A small, long lasting speaker that gets loud and can add a matching subwoofer, with a 30 hour battery.
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Specifications Side By Side
| Sony ULT Field 3 | Minirig 4 | |
|---|---|---|
| Price | $208.00 | $229.95 |
| Ranked | #71 of 177 in Medium Size Portable Bluetooth Speakers | #7 of 177 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | No | Yes |
| Battery Life | 24 hours (Manufacturer specified) | 30 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, AAC, LDAC | AAC, SBC |
| Bluetooth Version | 5.2 | 5.0 |
| Built-in Microphone | Yes | Yes |
| Dimensions | 10.1” x 4.4” x 3.1” (256 x 113 x 79 mm) | 4” x 2.9” (101.6 x 73 mm) (diameter x height) |
| Drivers | 1x 20mm tweeter + 1x 86mm x 46mm woofer | 70mm custom driver |
| EQ | Yes (App + ULT button) | Yes |
| IP Rating | IP67 | Splash resistant |
| Party Mode | Yes (Party Connect up to 100 speakers) | - |
| Power Bank | Yes (USB-C, 5V/1.5A) | Yes (USB-C) |
| Power Input | USB-C | USB-C |
| Stereo | Yes | No |
| Omnidirectional | No | Pointing up |
| TWS | Yes | Yes (Bluetooth or cable) |
| Weight | 2.6 lbs (1.2 kg) | 1.2 lbs (550 g) |
| Amplifier Power | 27W | 50W |
| Digital Aux Input | No | No |
| Strap | Yes (detachable shoulder strap) | - |
| Aux Latency | - | 0ms |
| Bass Extension (-10dB) | - | 56Hz |
| Bluetooth Latency | - | 60ms |
| Maximum SPL | - | 106dB (measured by Alan Ross Reviews) |
| Frequency Response | - | 60Hz - 18kHz (Manufacturer specified) |
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