Short answer: the Bose Soundlink Flex. It ranks #38 of 179 medium speakers by sound quality, rated 3.8/5, at $79.99; the Teufel Rockster Go 2 ranks #93, rated 3.2/5, and costs $99.99, so there is little reason to consider the other one.
The Bose Soundlink Flex is the better-sounding choice. A small, rugged waterproof speaker that survives drops and floats, with a warm, bass forward sound for casual outdoor use. The catch: Warm sounding with overly boosted bass which drowns out midrange detail.
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 supports AAC Bluetooth, which the Bose Soundlink Flex lacks. It has an adjustable EQ, which the Bose Soundlink Flex lacks. It plays in stereo from a single unit, unlike the Bose Soundlink Flex. The tradeoff: There is no companion app or 3.5 mm input.
Buy the Bose Soundlink Flex. It is rated higher for sound quality than the Teufel Rockster Go 2 and costs less, so only choose the other one for a particular feature it does better.
Looking for alternatives? See the complete Portable Bluetooth rankings.
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Specifications Side By Side
| Bose Soundlink Flex | Teufel Rockster Go 2 | |
|---|---|---|
| Price | $79.99 | $99.99 |
| Ranked | #38 of 179 in Medium Size Portable Bluetooth Speakers | #93 of 179 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes (Teufel Go) |
| Bass Extension (-10dB) | 56Hz | - |
| Battery Life | 12 hours (Manufacturer specified) | 15 hours, 28 with Eco Mode (Manufacturer specified) |
| Built-in Microphone | Yes | No |
| EQ | No | Yes |
| IP Rating | IP67 | IP67 |
| Bluetooth Latency | 33ms | - |
| Maximum SPL | 96dB (measured by Alan Ross Reviews) | - |
| 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 (589 g) | 1.6 lbs (735 g) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 4.2 | - |
| 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) |
| Drivers | 1x 60mm full-range driver + 2x passive radiators | 2x 50mm wide-band drivers + 1x 64mm passive radiator |
| Digital Aux Input | No | Yes (USB-C sound card) |
| Bluetooth Codecs | SBC | SBC, AAC |
| Aux Input | No | No |
| 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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