Short answer: the Tronsmart Mirtune C3 Plus. It ranks #75 of 150 medium speakers by sound quality, rated 3.3/5, at $49.99; the Sony ULT Field 1 ranks #86, rated 3.1/5, and costs $138, so there is not much of a tradeoff to weigh.
The case for the Tronsmart Mirtune C3 Plus: A racetrack woofer and a tweeter rated for 50W, with IPX7 waterproofing, Bluetooth 6.0, Auracast multi-speaker sync, stereo pairing, USB-C audio input, app EQ and a detachable lanyard, at 0.81 kg. Watch for: In side by side tests by Clinch Audio Bass and Mateusz Cholewa, the Xiaomi Sound Party and Soundcore Boom 3i sounded more refined and fuller, and listeners described the C3 Plus’s treble as dull.
The case for the Sony ULT Field 1: IP67 rated, survives drops and 1m submersion. The catch: Upper midrange peak, rolled off treble.
Buy the Tronsmart Mirtune C3 Plus. It is rated higher for sound quality than the Sony ULT Field 1 and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
Specifications Side By Side
| Tronsmart Mirtune C3 Plus | Sony ULT Field 1 | |
|---|---|---|
| Price | $49.99 | $138.00 |
| Ranked | #75 of 150 in Medium Size Portable Bluetooth Speakers | #86 of 150 in Medium Size Portable Bluetooth Speakers |
| Amplifier Power | 50W | - |
| App | Yes (Tronsmart) | Yes |
| Battery Life | 12 hours at 50% volume (Manufacturer specified) | 12 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | AAC, SBC |
| Bluetooth Version | 6.0 | 5.3 |
| Charging Time | 4 hours | - |
| Digital Aux Input | Yes (USB-C) | No |
| Dimensions | 8.3”H x 3.1”W x 3.3”D (210 x 80 x 85 mm) | 8.1” x 3” x 3” (206 x 77 x 76 mm) |
| Drivers | 1x racetrack woofer + 1x tweeter | 83mm x 42mm woofer, 16mm tweeter + passive radiator |
| EQ | Yes (app) | Yes |
| Frequency Response | 50Hz - 20kHz (Manufacturer specified) | - |
| IP Rating | IPX7 | IP67 |
| Omnidirectional | No | No |
| Party Mode | Yes (Auracast) | Yes (Party Connect up to 100 speakers) |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Strap | Yes (lanyard) | Yes (detachable strap) |
| TWS | Yes | Yes |
| Weight | 1.8 lbs (0.81 kg) | 1.4 lbs (650 g) |
| Aux Input | - | No |
| Built-in Microphone | - | Yes |
| Power Bank | - | No |
Related Speaker Comparisons
More worthwhile head-to-heads for Tronsmart Mirtune C3 Plus:
- Soundcore Motion 300 vs Tronsmart Mirtune C3 Plus
- JBL Charge 6 vs Tronsmart Mirtune C3 Plus
- JBL Flip 6 vs Tronsmart Mirtune C3 Plus
- JBL Flip 7 vs Tronsmart Mirtune C3 Plus
- Xiaomi Sound Party vs Tronsmart Mirtune C3 Plus
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.
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The Two Speakers In Full
Tronsmart Mirtune C3 Plus: $49.99 Tronsmart Best Buy eBay
Pros: A racetrack woofer and a tweeter rated for 50W, with IPX7 waterproofing, Bluetooth 6.0, Auracast multi-speaker sync, stereo pairing, USB-C audio input, app EQ and a detachable lanyard, at 0.81 kg.
Cons: In side by side tests by Clinch Audio Bass and Mateusz Cholewa, the Xiaomi Sound Party and Soundcore Boom 3i sounded more refined and fuller, and listeners described the C3 Plus’s treble as dull. Tronsmart rates the battery at only 12 hours at half volume. It is a mono unit with no aux input.
Full Tronsmart Mirtune C3 Plus review and specifications →
| Amplifier Power | 50W |
|---|---|
| App | Yes (Tronsmart) |
| Battery Life | 12 hours at 50% volume (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 6.0 |
| Charging Time | 4 hours |
| Digital Aux Input | Yes (USB-C) |
| Dimensions | 8.3”H x 3.1”W x 3.3”D (210 x 80 x 85 mm) |
| Drivers | 1x racetrack woofer + 1x tweeter |
| EQ | Yes (app) |
| Frequency Response | 50Hz - 20kHz (Manufacturer specified) |
| IP Rating | IPX7 |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Input | USB-C |
| Stereo | No |
| Strap | Yes (lanyard) |
| TWS | Yes |
| Weight | 1.8 lbs (0.81 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Clinch Audio Bass: Mirtune C3 Plus 50w VS Xioami Sound Party 50w
- Clinch Audio Bass: Mirtune C3 Plus 50w VS SoundCore Boom 3i 50w
- Techder Audios: Xiaomi Sound Party vs Tronsmart Mirtune C3 Plus - Real Sound & Bass Test! More from techderaudios →
- Mateusz Cholewa: Soundcore Boom 3i vs Tronsmart Mirtune C3 Plus More from Mateusz Cholewa →
- Importados Neto Rocha: Vale a pena pagar o dobro? Tronsmart C3 Plus vs JBL Flip 7
- GiT: Tronsmart Mirtune C3 vs C3+ blind test
- Head-to-Head Comparisons
- Tronsmart Mirtune C3 Plus vs Klipsch Nashville
- Tronsmart Mirtune C3 Plus vs JBL Charge 3
- Tronsmart Mirtune C3 Plus vs JBL Charge Essential
- Tronsmart Mirtune C3 Plus vs JBL Flip Essential 2
- Tronsmart Mirtune C3 Plus vs JBL Flip 5
- Tronsmart Mirtune C3 Plus vs Tronsmart Mirtune S100
- Tronsmart Mirtune C3 Plus vs JBL Grip
- Tronsmart Mirtune C3 Plus vs Sony ULT Field 3
- See all 33 comparisons
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 Tronsmart Mirtune C3
- Sony ULT Field 1 vs Tribit Xsound Surf
- Sony ULT Field 1 vs Sonos Roam
- See all 133 comparisons