Short answer: the Tronsmart Mirtune C3. It ranks #89 of 150 medium speakers by sound quality, rated 3.1/5, at $29.99; the Ultimate Ears Boom 4 ranks #99, rated 2.9/5, and costs $109.99, which makes this an easy call rather than a real tradeoff.
Why pick 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. The catch: 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.
What the Ultimate Ears Boom 4 does well: IP67 rated, floats, and finally charges via USB-C instead of the older Booms’ Micro-USB. The catch: Not much improvement over the old ones.
Buy the Tronsmart Mirtune C3. It is rated higher for sound quality than the Ultimate Ears Boom 4 and costs less, so only choose the other one for a particular feature it does better.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Tronsmart Mirtune C3 | Ultimate Ears Boom 4 | |
|---|---|---|
| Price | $29.99 | $109.99 |
| Ranked | #89 of 150 in Medium Size Portable Bluetooth Speakers | #99 of 150 in Medium Size Portable Bluetooth Speakers |
| Amplifier Power | 30W | - |
| App | Yes (Tronsmart) | Yes |
| Battery Capacity | 14.8Wh (7.4V, 2000mAh) | - |
| Battery Life | 12 hours at 50% volume (Manufacturer specified) | 15 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| Bluetooth Version | 6.0 | 5.1 |
| Charging Time | 2 hours | - |
| Digital Aux Input | Yes (USB-C) | No |
| Dimensions | 7.1”H x 2.8”W x 2.8”D (180 x 70 x 72 mm) | 7.2” x 2.9” x 2.9” (184 x 73 x 73 mm) |
| Drivers | 1x racetrack woofer + 1x tweeter | 2x 1.57” (40mm) active drivers + 2x 1.81” x 2.57” (46.1 x 65.2mm) passive radiators |
| EQ | Yes (app) | Yes (via app) |
| Frequency Response | 55Hz - 20kHz (Manufacturer specified) | - |
| IP Rating | IPX7 | IP67 |
| Omnidirectional | No | No |
| Party Mode | Yes (Auracast) | - |
| Power Input | USB-C | USB-C |
| Stereo | No | Yes |
| Strap | Yes (lanyard) | Yes (built-in loop) |
| TWS | Yes | Yes |
| Weight | 1.2 lbs (0.53 kg) | 1.4 lbs (620 g) |
| Built-in Microphone | - | No |
| Power Bank | - | No |
| Aux Input | - | No |
| Maximum SPL | - | 85dBC (Manufacturer specified) |
Related Speaker Comparisons
More worthwhile head-to-heads for Tronsmart Mirtune C3:
- Soundcore Motion 300 vs Tronsmart Mirtune C3
- JBL Charge 6 vs Tronsmart Mirtune C3
- JBL Flip 6 vs Tronsmart Mirtune C3
- JBL Flip 7 vs Tronsmart Mirtune C3
- Xiaomi Sound Party vs Tronsmart Mirtune C3
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: $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 Sony ULT Field 1
- 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 JBL Charge Essential
- See all 32 comparisons
Ultimate Ears Boom 4: $109.99 Amazon eBay
Older model: the Ultimate Ears Boom 3 (ranked lower, rated 2.9/5).
Pros: IP67 rated, floats, and finally charges via USB-C instead of the older Booms’ Micro-USB. 15 hour battery. Customizable EQ and speaker-pairing via the UE app.
Cons: Not much improvement over the old ones. Weak bass extension and thuddy bass. Gets distorted above 90%
Full Ultimate Ears Boom 4 review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Battery Life | 15 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.1 |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 7.2” x 2.9” x 2.9” (184 x 73 x 73 mm) |
| Drivers | 2x 1.57” (40mm) active drivers + 2x 1.81” x 2.57” (46.1 x 65.2mm) passive radiators |
| EQ | Yes (via app) |
| IP Rating | IP67 |
| Maximum SPL | 85dBC (Manufacturer specified) |
| Omnidirectional | No |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | Yes (built-in loop) |
| TWS | Yes |
| Weight | 1.4 lbs (620 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Ultimate Ears Boom 4 vs Ultimate Ears Boom 3
- Ultimate Ears Boom 4 vs Ultimate Ears Wonderboom
- Ultimate Ears Boom 4 vs Klipsch Groove/Heritage Groove
- Ultimate Ears Boom 4 vs Ultimate Ears Wonderboom 2
- Ultimate Ears Boom 4 vs Ultimate Ears Wonderboom 3
- Ultimate Ears Boom 4 vs DBSONO X-Blast F37
- Ultimate Ears Boom 4 vs Ultimate Ears Wonderboom 4
- Ultimate Ears Boom 4 vs Sony SRS-XE300
- See all 133 comparisons