Short answer: the Bose Soundlink Flex 2nd gen. It ranks #37 of 179 medium speakers by sound quality, rated 3.8/5, at $159. The Teufel Rockster Go 2 ranks #93, rated 3.2/5, at $99.99, $59.01 cheaper, a saving that is not big enough to make up the sound-quality gap.
The Bose Soundlink Flex 2nd gen is the better-sounding, lighter pick. A small, rugged waterproof speaker with clear, well balanced mids, app EQ, aptX Adaptive and stereo pairing with a second unit. At 1.3 lbs (586 g) it weighs noticeably less than the Teufel Rockster Go 2 at 1.6 lbs (735 g). It supports aptX Adaptive Bluetooth, which the Teufel Rockster Go 2 lacks. The tradeoff: One Flex remains mono and cannot deliver genuine low-bass rumble; RTINGS also found the elevated treble can turn hi-hats and other high-frequency detail piercing.
What the Teufel Rockster Go 2 does well: A light, rugged waterproof speaker with very long battery life in eco mode, stereo pairing and a tripod mount. It plays in stereo from a single unit, unlike the Bose Soundlink Flex 2nd gen. Watch for: There is no companion app or 3.5 mm input.
Buy the Bose Soundlink Flex 2nd gen. It is rated higher for sound quality, and the $59.01 you would save on the Teufel Rockster Go 2 does not close the gap.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
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Specifications Side By Side
| Bose Soundlink Flex 2nd gen | Teufel Rockster Go 2 | |
|---|---|---|
| Price | $159.00 | $99.99 |
| Ranked | #37 of 179 in Medium Size Portable Bluetooth Speakers | #93 of 179 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes (Teufel Go) |
| Battery Life | 12 hours (Manufacturer specified) | 15 hours, 28 with Eco Mode (Manufacturer specified) |
| Built-in Microphone | Yes | No |
| EQ | Yes (3 band) | Yes |
| IP Rating | IP67 | IP67 |
| Party Mode | Yes (Bose Party mode) | Yes (Party Link, up to 100 speakers) |
| Power Input | USB-C | USB-C |
| Stereo | No | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 1.3 lbs (586 g) | 1.6 lbs (735 g) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | - |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) | 8.3” x 4.3” x 2.4” (211 x 109 x 61 mm) |
| Aux Input | No | No |
| Drivers | 60mm full-range driver with passive radiators | 2x 50mm wide-band drivers + 1x 64mm passive radiator |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive | SBC, AAC |
| Digital Aux Input | No | Yes (USB-C sound card) |
| Strap | Yes (built-in loop) | Yes (detachable strap) |
| Power Bank | - | No |
| USB Playback | - | No |
| Amplifier Power | - | 8W |
| Frequency Response | - | 60Hz - 20kHz (Manufacturer specified) |
| Charging Time | - | 2.5 hours (Manufacturer specified) |
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