Short answer: the EarFun Uboom L on sound, with a latency catch. It was tuned by Oluv and, the notes say, he knocked it out of the park, though latency is high at 400ms unless low latency mode drops it to 66ms, and that mode does not work when two speakers are TWS paired. The Bose Soundlink Flex 2nd gen sounds pretty much identical to the 1st gen but is not stereo.
Buy the EarFun Uboom L. It is rated higher for sound quality than the Bose Soundlink Flex 2nd gen and costs less, so only choose the other one for a particular feature it does better.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
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Specifications Side By Side
| Bose Soundlink Flex 2nd gen | EarFun Uboom L | |
|---|---|---|
| Price | $159.00 | $49.79 after coupon UBOOMLWC |
| Ranked | #37 of 179 in Medium Size Portable Bluetooth Speakers | #2 of 179 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes (firmware >= 1.2.6) |
| Battery Life | 12 hours (Manufacturer specified) | 16 hours (Manufacturer specified) |
| Built-in Microphone | Yes | Yes |
| EQ | Yes (3 band) | Yes (10 band, firmware >= 1.2.6) |
| IP Rating | IP67 | IP67 |
| Party Mode | Yes (Bose Party mode) | No |
| Power Input | USB-C | USB-C |
| Stereo | No | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 1.3 lbs (586 g) | 1.4 lbs (650 g) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 5.0 |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) | 3.1” x 8.3” x 2.8” (78 x 210 x 72 mm) |
| Aux Input | No | Yes |
| Drivers | 60mm full-range driver with passive radiators | 2x 55mm drivers + 2x passive radiators |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive | AAC, SBC |
| Digital Aux Input | No | No |
| Strap | Yes (built-in loop) | - |
| Aux Latency | - | 216ms |
| Bass Extension (-10dB) | - | 56Hz |
| Bluetooth Latency | - | 400ms normal / 66ms low latency mode |
| Maximum SPL | - | 103dB (measured by Alan Ross Reviews) |
| Power Bank | - | No |
| Amplifier Power | - | 28W |
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