Short answer: the Bose Soundlink Flex. It ranks #38 of 179 medium speakers by sound quality, rated 3.8/5, at $79.99; the Tronsmart Mirtune S100 ranks #97, rated 3.1/5, at $79.99. Close enough in price that the sound-quality gap is the deciding factor.
The Bose Soundlink Flex is the better-sounding, deeper-bass option. A small, rugged waterproof speaker that survives drops and floats, with a warm, bass forward sound for casual outdoor use. Its bass reaches about 56Hz before falling 10dB, against 64Hz for the Tronsmart Mirtune S100. At 1.3 lbs (589 g) it weighs much less than the Tronsmart Mirtune S100 at 3 lbs (1.36 kg). Watch for: Warm sounding with overly boosted bass which drowns out midrange detail.
The Tronsmart Mirtune S100 is the longer-running pick. A waterproof speaker with long battery life for outdoor and casual listening. It is rated for 20 hours of battery against 12 for the Bose Soundlink Flex. It keeps a wired aux input, which the Bose Soundlink Flex lacks. It has an adjustable EQ, which the Bose Soundlink Flex lacks.
Buy the Bose Soundlink Flex. It is rated higher for sound quality than the Tronsmart Mirtune S100 at the same price, 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.
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Specifications Side By Side
| Bose Soundlink Flex | Tronsmart Mirtune S100 | |
|---|---|---|
| Price | $79.99 | $79.99 |
| Ranked | #38 of 179 in Medium Size Portable Bluetooth Speakers | #97 of 179 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Bass Extension (-10dB) | 56Hz | ~64Hz |
| Battery Life | 12 hours (Manufacturer specified) | 20 hours (Manufacturer specified) |
| Built-in Microphone | Yes | Yes |
| EQ | No | Yes |
| IP Rating | IP67 | IPX7 |
| Bluetooth Latency | 33ms | - |
| Maximum SPL | 96dB (measured by Alan Ross Reviews) | - |
| Party Mode | Yes (Bose Party mode) | - |
| Power Input | USB-C | USB-C |
| Stereo | No | Partially |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 1.3 lbs (589 g) | 3 lbs (1.36 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 4.2 | 5.3 |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) | 9.1” x 3.5” x 3.9” (231 x 88 x 100 mm) |
| Drivers | 1x 60mm full-range driver + 2x passive radiators | 20W drivers |
| Digital Aux Input | No | No |
| Bluetooth Codecs | SBC | SBC |
| Aux Input | No | Yes |
| Strap | Yes (built-in loop) | - |
| Wi-Fi | - | No |
| Frequency Response | - | 50Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | - | 50W |
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