Short answer: the Harman Kardon Luna if sound quality matters most, the Tronsmart Mirtune C3 Plus if price matters most. The Harman Kardon Luna ranks #26 of 182 medium speakers, rated 4.0/5, at $290.99. The Tronsmart Mirtune C3 Plus ranks #84, rated 3.3/5, at $49.99, $241 cheaper.
The Harman Kardon Luna is the better-sounding pick. A fully waterproof speaker with fairly balanced, bass rich sound, a separate tweeter, and stereo pairing with a second unit. The catch: Boosted bass, and less detailed than higher-ranked speakers.
The Tronsmart Mirtune C3 Plus is the lighter option. An affordable waterproof speaker with a separate tweeter, app EQ, Auracast linking, stereo pairing and USB-C audio input. At 1.8 lbs (810 g) it weighs noticeably less than the Harman Kardon Luna at 2.5 lbs (1.13 kg). It has an adjustable EQ, which the Harman Kardon Luna lacks. The catch: 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.
Buy the Harman Kardon Luna when sound quality outweighs the price for you, and the Tronsmart Mirtune C3 Plus when the price outweighs sound quality instead.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
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
| Harman Kardon Luna | Tronsmart Mirtune C3 Plus | |
|---|---|---|
| Price | $290.99 | $49.99 |
| Ranked | #26 of 182 in Medium Size Portable Bluetooth Speakers | #84 of 182 in Medium Size Portable Bluetooth Speakers |
| App | No | Yes (Tronsmart) |
| Aux Input | No | No |
| Bass Extension (-10dB) | 57Hz | - |
| Battery Life | 12 hours (Manufacturer specified) | 12 hours at 50% volume (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| EQ | No | Yes (app) |
| IP Rating | IP67 | IPX7 |
| MicroSD Playback | No | - |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | - |
| Weight | 2.5 lbs (1.13 kg) | 1.8 lbs (0.81 kg) |
| Bluetooth Version | 5.3 | 6.0 |
| Dimensions | 8.3” x 3.1” x 3.1” (210 x 78 x 80 mm) | 8.3”H x 3.1”W x 3.3”D (210 x 80 x 85 mm) |
| Drivers | 48mm x 90mm woofer, 20mm tweeter | 1x racetrack woofer + 1x tweeter |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) | 50Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | 40W | 50W |
| Digital Aux Input | No | Yes (USB-C) |
| Charging Time | - | 4 hours |
| Party Mode | - | Yes (Auracast) |
| Strap | - | Yes (lanyard) |
Where the Ratings Come From
- Harman Kardon Luna: reviews by Oluv, Alan Ross and Mateusz Cholewa.
- Tronsmart Mirtune C3 Plus: reviews by Oluv, Mateusz Cholewa and Techder Audios.
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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