Short answer: the Minirig 4 for sound quality and battery life, the Bose Soundlink Flex 2nd gen for durability and dependability. The Minirig 4 ranks #35 of 142 medium speakers at $229.95. The Flex 2nd gen ranks #6 at $159, $70.95 cheaper.
The Flex 2nd gen is a refinement, not a reinvention. Its clear, well-balanced midrange keeps voices and instruments intelligible, and the second generation adds a Bose app with 3-band EQ, better-placed controls, and stereo pairing with a second Flex. It also supports AAC and aptX Adaptive, not just SBC, making it a stronger wireless option than most small rivals. The honest tradeoff is that it remains mono, can’t produce genuine low-bass rumble, and RTINGS found the elevated treble can turn hi-hats piercing. Battery life is a modest 12 hours.
The Minirig 4 wins on modularity and stamina but carries real risk. It’s modular, so you can easily attach a subwoofer, it finally added USB-C charging, and it dynamically adjusts its sound depending on whether it’s facing forward or standing upward. Battery life is rated at 30 hours, well ahead of the Flex. But it calls itself only splash resistant with no official water rating, versus the Flex’s true IP67 rating that survives brief submersion. Its app is described as buggy, and it has reported reliability issues more often than any other speaker on the site.
Everything else matches: both charge over USB-C, include a built-in microphone, and support TWS pairing.
Buy the Minirig 4 if measured sound quality, longer battery life, and the ability to add a subwoofer matter most, and you can accept the durability and reliability tradeoffs.
Buy the Bose Soundlink Flex 2nd gen if you want genuine water resistance and a track record of reliability at a lower price, even with shorter battery life and less low-end extension.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Bose Soundlink Flex 2nd gen | Minirig 4 | |
|---|---|---|
| Price | $159.00 | $229.95 |
| Ranked | #35 of 142 in Medium Size Portable Bluetooth Speakers | #6 of 142 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Battery Life | 12 hours (Manufacturer specified) | 30 hours (Manufacturer specified) |
| Built-in Microphone | Yes | Yes |
| EQ | Yes (3 band) | Yes |
| IP Rating | IP67 | Splash resistant |
| Party Mode | Yes (Bose Party mode) | - |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Omnidirectional | No | Pointing up |
| TWS | Yes | Yes (Bluetooth or cable) |
| Weight | 1.3 lbs (586 g) | 1.2 lbs (550 g) |
| Bluetooth Version | 5.3 | 5.0 |
| Dimensions | 7.9" x 3.5" x 2" (201 x 90 x 52 mm) | 4" x 2.9" (101.6 x 73 mm) (diameter x height) |
| Aux Input | No | Yes |
| Drivers | 60mm full-range driver with passive radiators | 70mm custom driver |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive | AAC, SBC |
| Digital Aux Input | No | No |
| Aux Latency | - | 0ms |
| Bass Extension (-10dB) | - | 56Hz |
| Bluetooth Latency | - | 60ms |
| Maximum SPL | - | 106dB (measured by Alan Ross Reviews) |
| Power Bank | - | Yes (USB-C) |
| Frequency Response | - | 60Hz - 18kHz (Manufacturer specified) |
| Amplifier Power | - | 50W |
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Prices on this page were last checked September 23, 2026 at 11:24 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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The Two Speakers In Full
Bose Soundlink Flex 2nd gen: $159.00 Amazon eBay
Pros: A very portable 586g, IP67-rated speaker with a clear, well-balanced midrange that keeps voices and instruments intelligible. The second generation adds a Bose app with 3-band EQ, better-placed controls and stereo pairing with another Bose Soundlink Flex 2nd gen. It supports AAC and aptX Adaptive in addition to SBC, making it a stronger wireless option than most small rivals.
Cons: 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. The claimed battery life is only 12 hours, and some owners report accelerated standby drain after firmware updates. It is expensive for its size, so the added app and codec support, not a transformational sound upgrade over the original, are the main reasons to choose it.
Full Bose Soundlink Flex 2nd gen review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 7.9" x 3.5" x 2" (201 x 90 x 52 mm) |
| Drivers | 60mm full-range driver with passive radiators |
| EQ | Yes (3 band) |
| IP Rating | IP67 |
| Omnidirectional | No |
| Party Mode | Yes (Bose Party mode) |
| Power Input | USB-C |
| Stereo | No |
| TWS | Yes |
| Weight | 1.3 lbs (586 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Joy & Oluv’Sone: Bose Soundlink Flex 2nd gen vs Flex More from Oluv’Sone →
- Oluv Patreon: Bose Soundlink Flex 2nd gen - sound demo
- Tô Thái Trí Hùng: Unbox & Sound Test - Bose Soundlink Flex 2
- Joy & Oluv’Sone: Bose Soundlink Flex 2nd gen & Soundcore Motion 300 sound test
- Alan Ross: Hall of Fame classic vs latest Bose tech! More from alanrossreviews →
- CEONTHEMAKING: Bose Soundlink Flex 2nd Gen VS Marshall Emberton III - What’s NEW?? More from CEONTHEMAKING →
- Alan Ross - The Anti Shill!: Small speaker, mighty sound, The Flex gen 2 shatters physics!
- Head-to-Head Comparisons
- Bose Soundlink Flex 2nd gen vs Bose Soundlink Flex
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- Bose Soundlink Flex 2nd gen vs Soundcore Motion 100
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Minirig 4: $229.95 Amazon eBay
Pros: Modular, can easily attach a subwoofer. Finally USB-C charging. Dynamically changes sound based on forward facing or upward facing orientation. Measured bass extension of 56Hz (-10dB).
Cons: Calls itself splash resistant and has no official water rating. App is buggy. A bit expensive. Has reliability issues more often than any other speaker
Full Minirig 4 review and specifications →
| Amplifier Power | 50W |
|---|---|
| App | Yes |
| Aux Input | Yes |
| Aux Latency | 0ms |
| Bass Extension (-10dB) | 56Hz |
| Battery Life | 30 hours (Manufacturer specified) |
| Bluetooth Codecs | AAC, SBC |
| Bluetooth Latency | 60ms |
| Bluetooth Version | 5.0 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 4" x 2.9" (101.6 x 73 mm) (diameter x height) |
| Drivers | 70mm custom driver |
| EQ | Yes |
| Frequency Response | 60Hz - 18kHz (Manufacturer specified) |
| IP Rating | Splash resistant |
| Maximum SPL | 106dB (measured by Alan Ross Reviews) |
| Omnidirectional | Pointing up |
| Power Bank | Yes (USB-C) |
| Power Input | USB-C |
| Stereo | No |
| TWS | Yes (Bluetooth or cable) |
| Weight | 1.2 lbs (550 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons