Short answer: the Harman Kardon Luna. It ranks #26 of 175 medium speakers by sound quality, rated 4.0/5, at $290.99. The Bose Soundlink Flex ranks #38, rated 3.8/5, at $159, $131.99 cheaper, which does not close the gap in sound quality.
The case for the Harman Kardon Luna: Harman Kardon Luna uses 48mm x 90mm woofer, 20mm tweeter. The tradeoff: Bass is limited by its 57Hz specification.
The Bose Soundlink Flex is the lighter pick. IP67 rated; rugged enough to survive drops from several feet and floats. At 1.3 lbs (589 g) it weighs much less than the Harman Kardon Luna at 2.5 lbs (1.13 kg). Watch for: Warm sounding with overly boosted bass which drowns out midrange detail.
Buy the Harman Kardon Luna. It is rated higher for sound quality, and the $131.99 saving on the Bose Soundlink Flex is not enough to make up the difference.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Luna | Bose Soundlink Flex | |
|---|---|---|
| Price | $290.99 | $159.00 |
| Ranked | #26 of 175 in Medium Size Portable Bluetooth Speakers | #38 of 175 in Medium Size Portable Bluetooth Speakers |
| App | No | Yes |
| Aux Input | No | No |
| Bass Extension (-10dB) | 57Hz | 56Hz |
| Battery Life | 12 hours (Manufacturer specified) | 12 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| EQ | No | No |
| IP Rating | IP67 | IP67 |
| MicroSD Playback | No | - |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | - |
| Weight | 2.5 lbs (1.13 kg) | 1.3 lbs (589 g) |
| Bluetooth Version | 5.3 | 4.2 |
| Dimensions | 8.3” x 3.1” x 3.1” (210 x 78 x 80 mm) | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) |
| Drivers | 48mm x 90mm woofer, 20mm tweeter | 1x 60mm full-range driver + 2x passive radiators |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) | - |
| Amplifier Power | 40W | - |
| Digital Aux Input | No | No |
| Built-in Microphone | - | Yes |
| Bluetooth Latency | - | 33ms |
| Maximum SPL | - | 96dB (measured by Alan Ross Reviews) |
| Party Mode | - | Yes (Bose Party mode) |
| Strap | - | Yes (built-in loop) |
Watch Them Compared
Videos and reviews that test both speakers side by side.
Related Speaker Comparisons
How Harman Kardon Luna compares with other leading options:
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- Soundcore Motion 300 vs Harman Kardon Luna
- Soundcore Motion+ vs Harman Kardon Luna
- Soundcore Boost “upgraded” 2021 vs Harman Kardon Luna
- Harman Kardon Luna vs Minirig 4
Prices on this page were last checked October 12, 2026 at 4:13 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
Harman Kardon Luna: $290.99 Amazon $290.99 eBay
Newer model: the Harman Kardon Luna 2, ranked higher, rated 4.1/5, released Mar 2026. It adds app control and adjustable EQ. See every Harman Kardon Luna generation.
Pros: Harman Kardon Luna uses 48mm x 90mm woofer, 20mm tweeter. Its 1.13 kg, claimed 12 hours (Manufacturer specified) battery life, IP67 protection and mono playback make it a practical option for its intended room or portable use. The sound is fairly balanced apart from the boosted bass. Measured bass extension of 57Hz (-10dB).
Cons: Bass is limited by its 57Hz specification. There is no companion app. No EQ adjustment. Boosted bass, and less detailed than higher-ranked speakers.
Full Harman Kardon Luna review and specifications →
| Released | Sep 2023 (3 years ago) |
|---|---|
| Amplifier Power | 40W |
| App | No |
| Aux Input | No |
| Bass Extension (-10dB) | 57Hz |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 8.3” x 3.1” x 3.1” (210 x 78 x 80 mm) |
| Drivers | 48mm x 90mm woofer, 20mm tweeter |
| EQ | No |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) |
| IP Rating | IP67 |
| MicroSD Playback | No |
| Omnidirectional | No |
| Power Input | USB-C |
| Stereo | No |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 2.5 lbs (1.13 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Oluv Patreon: Harman Kardon Luna - sound demo More from Oluv’Sone →
- Alan Ross - The Anti Shill!: Onyx Studio 9 or Go Play 3? Or even the HK Luna?? More from alanrossreviews →
- Alan Ross Reviews: Beats Pill vs Harman Luna vs Bose Flex vs Soundcore Motion Plus
- Mateusz Cholewa: Harman Kardon Luna 2 UNBOXING vs HK Luna Short Test More from Mateusz Cholewa →
- Storytripper HD: Harman Kardon Luna vs Luna 2 More from storytripperhd →
- Storytripper HD: Klipsch Nashville vs Harman Kardon Luna vs Soundcore Motion 300
- Storytripper HD: Huawei Sound Joy 2 vs Tribit XSound Plus 2 vs Harman Kardon Luna
- Head-to-Head Comparisons
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Bose Soundlink Flex: $159.00 Amazon $159.00 eBay
Newer model: the Bose Soundlink Flex 2nd gen, ranked higher, rated 3.8/5, released Sep 2024. It adds adjustable EQ, AAC and aptX Adaptive. See every Bose SoundLink Flex, Micro, Max and Plus generation.
Pros: IP67 rated; rugged enough to survive drops from several feet and floats. Around 12 hours of battery at moderate volume. Measured bass extension of 56Hz (-10dB).
Cons: Not stereo. Warm sounding with overly boosted bass which drowns out midrange detail
Full Bose Soundlink Flex review and specifications →
| Released | Oct 2021 (5 years ago) |
|---|---|
| App | Yes |
| Aux Input | No |
| Bass Extension (-10dB) | 56Hz |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Latency | 33ms |
| Bluetooth Version | 4.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) |
| Drivers | 1x 60mm full-range driver + 2x passive radiators |
| EQ | No |
| IP Rating | IP67 |
| Maximum SPL | 96dB (measured by Alan Ross Reviews) |
| Omnidirectional | No |
| Party Mode | Yes (Bose Party mode) |
| Power Input | USB-C |
| Stereo | No |
| Strap | Yes (built-in loop) |
| TWS | Yes |
| Weight | 1.3 lbs (589 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Joy & Oluv’Sone: Bose Soundlink Flex 2nd gen vs Flex More from Oluv’Sone →
- Joy & Oluv’Sone: JBL, Bose, B&O, Sonos, Earfun, SoundCore… which portable speaker sounds best?
- Oluv Patreon: Bose Soundlink Plus & Flex compared
- Oluv Patreon: Soundcore Motion 300 = Bose Soundlink Flex = Earfun UBoom L?
- Alan Ross Reviews: Bose Soundlink Flex or Beosound A1 (1st gen) - ultimate compact speaker 😇 More from alanrossreviews →
- Alan Ross Reviews: Bose Soundlink Flex vs Minirig MK3 and Marshall Emberton - best bluetooth speaker?
- Alan Ross - The Anti Shill!: Small speaker, mighty sound, The Flex gen 2 shatters physics!
- Alan Ross Reviews: Travel Speakers! Soundcore Motion 300 or Bose Flex or Tribit Stormbow Flow
- Alan Ross Reviews: Bose Soundlink Flex Review! vs JBL Flip 6 and JBL Charge 5. Travel heaven?? 🤞
- Alan Ross Reviews: Bose Soundlink Flex vs Soundcore Boost vs Bogasing M4 - cheap or Bose?
- Alan Ross Reviews: Bose Soundlink Flex or JBL Flip 6 (eq adjusted) or Denon Envaya - best speaker for travel!
- Alan Ross Reviews: 1 million views! Best Budget Tws? Tozo Pa1 Review and sound test
- Alan Ross Reviews: Beats Pill vs Harman Luna vs Bose Flex vs Soundcore Motion Plus
- Alan Ross Reviews: Tribit Xsound Mega vs the world! (JBL Charge 5, Bose Flex, Sony XB33, LG PL7) 👍
- Alan Ross Reviews: Tribit Stormbox Flow has deeper bass than the Bose Flex but………..
- Jay’s Straight Up Reviews & More: Tribit Stormbox Flow vs Soundcore Motion 300 (LDAC) 😵 Budget Bose Soundlink Flex "Inspired" Speakers More from JaysStraightUpReviews →
- Danny Pops: BEST Bose Speaker?? Bose Soundlink Flex vs micro, Color II, and revolve + More from DannyPops →
- Danny Pops: BEST Bose Speaker? Bose is getting lazy.
- Patricio Benadon: Bose SoundLink Flex vs. Mini 2 SE. Music audio quality sound test. Listen 4 different genres!
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