Short answer: the Tronsmart Mirtune C3. Both are rated 3.1/5 for sound quality (#89 and #86 of 150 medium speakers), and the Tronsmart Mirtune C3 costs $29.99 against $138 for the Sony ULT Field 1, with sound quality a draw, the lower price decides it.
Why pick the Sony ULT Field 1: IP67 rated, survives drops and 1m submersion. Watch for: Upper midrange peak, rolled off treble.
The case for the Tronsmart Mirtune C3: Small and light at 530 g, with a racetrack driver and a tweeter rated for 30W, IPX7 waterproofing, Bluetooth 6.0, Auracast multi-speaker sync, stereo pairing, USB-C audio input, app EQ and a lanyard. Watch for: In GiT’s three way blind test it came behind the Creative Muvo Go and Xiaomi Sound Outdoor, sounding good only on sparse tracks, and listeners in AudioPro Reviews’ comparison found the JBL Flip 6 fuller with more bass.
Buy the Tronsmart Mirtune C3. Both are rated the same for sound quality, and it costs $108.01 less than the Sony ULT Field 1.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
Specifications Side By Side
| Sony ULT Field 1 | Tronsmart Mirtune C3 | |
|---|---|---|
| Price | $138.00 | $29.99 |
| Ranked | #86 of 150 in Medium Size Portable Bluetooth Speakers | #89 of 150 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes (Tronsmart) |
| Aux Input | No | - |
| Battery Life | 12 hours (Manufacturer specified) | 12 hours at 50% volume (Manufacturer specified) |
| Built-in Microphone | Yes | - |
| EQ | Yes | Yes (app) |
| IP Rating | IP67 | IPX7 |
| Party Mode | Yes (Party Connect up to 100 speakers) | Yes (Auracast) |
| Power Bank | No | - |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 1.4 lbs (650 g) | 1.2 lbs (0.53 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | AAC, SBC | SBC |
| Bluetooth Version | 5.3 | 6.0 |
| Dimensions | 8.1” x 3” x 3” (206 x 77 x 76 mm) | 7.1”H x 2.8”W x 2.8”D (180 x 70 x 72 mm) |
| Drivers | 83mm x 42mm woofer, 16mm tweeter + passive radiator | 1x racetrack woofer + 1x tweeter |
| Digital Aux Input | No | Yes (USB-C) |
| Strap | Yes (detachable strap) | Yes (lanyard) |
| Amplifier Power | - | 30W |
| Battery Capacity | - | 14.8Wh (7.4V, 2000mAh) |
| Charging Time | - | 2 hours |
| Frequency Response | - | 55Hz - 20kHz (Manufacturer specified) |
Related Speaker Comparisons
More worthwhile head-to-heads for Sony ULT Field 1:
- Sony ULT Field 1 vs Earfun Uboom L
- Sony ULT Field 1 vs Soundcore Motion 300
- Soundcore Motion+ vs Sony ULT Field 1
- Soundcore Boost “upgraded” 2021 vs Sony ULT Field 1
- Sony ULT Field 1 vs Minirig 4
Prices on this page were last checked September 30, 2026 at 2:57 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.
As an eBay Partner, we may be compensated if you make a purchase.
The Two Speakers In Full
Sony ULT Field 1: $138.00 Amazon eBay
Older models: the Sony XB23 (ranked higher, rated 3.3/5) and the Sony SRS-XB20 (ranked lower, rated 2.8/5).
Pros: IP67 rated, survives drops and 1m submersion. Real-world battery around 28+ hours with ULT (bass boost) mode off. Stereo-pairs with a second ULT Field 1.
Cons: Upper midrange peak, rolled off treble
Full Sony ULT Field 1 review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | AAC, SBC |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 8.1” x 3” x 3” (206 x 77 x 76 mm) |
| Drivers | 83mm x 42mm woofer, 16mm tweeter + passive radiator |
| EQ | Yes |
| IP Rating | IP67 |
| Omnidirectional | No |
| Party Mode | Yes (Party Connect up to 100 speakers) |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | No |
| Strap | Yes (detachable strap) |
| TWS | Yes |
| Weight | 1.4 lbs (650 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Sony ULT Field 1 vs JBL Grip
- Sony ULT Field 1 vs Treblab HD77
- Sony ULT Field 1 vs Tribit Xsound Go
- Sony ULT Field 1 vs Tronsmart Mirtune S100
- Sony ULT Field 1 vs KEF Muo gen2
- Sony ULT Field 1 vs Tribit Xsound Surf
- Sony ULT Field 1 vs Sonos Roam
- Sony ULT Field 1 vs Tribit Stormbox 2
- See all 133 comparisons
Tronsmart Mirtune C3: $29.99 Tronsmart eBay
Pros: Small and light at 530 g, with a racetrack driver and a tweeter rated for 30W, IPX7 waterproofing, Bluetooth 6.0, Auracast multi-speaker sync, stereo pairing, USB-C audio input, app EQ and a lanyard.
Cons: In GiT’s three way blind test it came behind the Creative Muvo Go and Xiaomi Sound Outdoor, sounding good only on sparse tracks, and listeners in AudioPro Reviews’ comparison found the JBL Flip 6 fuller with more bass. Tronsmart rates the battery at 12 hours at half volume. It is a mono unit with no aux input.
Full Tronsmart Mirtune C3 review and specifications →
| Amplifier Power | 30W |
|---|---|
| App | Yes (Tronsmart) |
| Battery Capacity | 14.8Wh (7.4V, 2000mAh) |
| Battery Life | 12 hours at 50% volume (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 6.0 |
| Charging Time | 2 hours |
| Digital Aux Input | Yes (USB-C) |
| Dimensions | 7.1”H x 2.8”W x 2.8”D (180 x 70 x 72 mm) |
| Drivers | 1x racetrack woofer + 1x tweeter |
| EQ | Yes (app) |
| Frequency Response | 55Hz - 20kHz (Manufacturer specified) |
| IP Rating | IPX7 |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Input | USB-C |
| Stereo | No |
| Strap | Yes (lanyard) |
| TWS | Yes |
| Weight | 1.2 lbs (0.53 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Tronsmart Mirtune C3 vs Tribit Xsound Go
- Tronsmart Mirtune C3 vs Tribit Stormbox 2
- Tronsmart Mirtune C3 vs Soundcore 2
- Tronsmart Mirtune C3 vs JBL Grip
- Tronsmart Mirtune C3 vs Tronsmart Mirtune S100
- Tronsmart Mirtune C3 vs Ultimate Ears Wonderboom 4
- Tronsmart Mirtune C3 vs Ultimate Ears Boom 4
- Tronsmart Mirtune C3 vs JBL Charge Essential
- See all 32 comparisons