Short answer: the Earfun Uboom X. It ranks #1 of 70 boombox speakers at $128; the Harman Kardon Onyx Studio 9 ranks #13 and costs $186.99, so there is not much of a tradeoff to weigh.
On the Earfun Uboom X side: Tuned by Oluv and he knocked it out of the park again. Set against that: The out of the box 0.33 firmware and EQ sounds horrible.
The case for the Harman Kardon Onyx Studio 9: Auracast multi-speaker connection alongside classic stereo pairing. Set against that: Slight recessed mids, boost in the upper mids, rolled off upper treble.
One note: the Earfun Uboom X is discontinued, but it still ranks #1 of 70 boombox speakers, ahead of most of what is still sold new, so it is worth considering used.
Buy the Earfun Uboom X if the ranking matters more than the price. Buy the Harman Kardon Onyx Studio 9 if the price matters more than the ranking.
Specifications Side By Side
| Earfun Uboom X | Harman Kardon Onyx Studio 9 | |
|---|---|---|
| Price | $128 Discontinued | $186.99 |
| Ranked | #1 of 70 in Boombox Size Portable Bluetooth Speakers | #13 of 70 in Boombox Size Portable Bluetooth Speakers |
| App | Yes (Earfun Audio app) | Yes (Harman Kardon One app) |
| Aux Input | Yes | - |
| Aux Latency | 16ms | - |
| Bass Extension (-10dB) | ~38Hz | 41Hz |
| Battery Life | 30 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Bluetooth Codecs | AAC, SBC | SBC |
| Built in Microphone | Yes | - |
| EQ | Yes (App EQ) | Yes (App EQ) |
| IP Rating | IP67 | None |
| Bluetooth Latency | SBC Video mode 48ms, AAC Video mode 128ms, SBC 112ms, AAC 176ms | - |
| Max Volume | 110dB | 101dB |
| Party Mode | Yes (Up to 50 speakers) | Yes (Auracast) |
| Power Bank | Yes | - |
| Power Input | USB-C | USB-C |
| TWS | Yes | Yes |
| Weight | 9 lbs / 4.1 kg | 9.3 lbs / 4.2 kg |
| Stereo | Yes | Yes |
| USB Playback | No | No |
| FM Tuner | No | - |
| Bluetooth Version | 5.3 | 5.3 |
| Output Power | 80W | 50W RMS |
| Dimensions | 15.75" x 5.91" x 8.46" (400 x 150 x 215 mm) | 11.39" x 11.32" x 5.12" (289.2 x 287.5 x 130 mm) |
| Drivers | 2x 102mm (4") woofers + 2x 20mm tweeters | 120mm woofer + 3x 20mm tweeters |
| Discontinued | Yes | - |
The Two Speakers In Full
Earfun Uboom X: $128 Discontinued Myearfun Amazon
Pros: Tuned by Oluv and he knocked it out of the park again. Deeper bass than the Stormbox Blast. Extremely neutral, possibly the best of any modern Bluetooth speaker slightly behind the Vifa Helsinki. This is the only speaker that sounds correct at every single volume level due to Oluv’s individual EQ settings at each volume level. Other speakers will need a different EQ at each volume level. Amazing sounding at low levels as it boosts bass and treble at low levels to account for the equal-loudness contour. Just considering the midrange and treble, this speaker is better sounding than the Earfun Uboom L.
Cons: The out of the box 0.33 firmware and EQ sounds horrible. Some people have mentioned sound interruption issues when using 2 in TWS, I don’t have this issue with my Pixel 7 Pro, try disabling AAC in that case. Discontinued.
Setup: Please update it using the Earfun app (Android or iOS) and select an Oluv EQ. The Earfun app has sound profiles created by Oluv for Studio, Indoor, Indoor+, Outdoor, Outdoor+, BOOM xxX, and Ground 0 which are all fantastic. Oluv has a newer firmware pack that brings it up a few more notches of neutral
| App | Yes (Earfun Audio app) |
|---|---|
| Aux Input | Yes |
| Aux Latency | 16ms |
| Bass Extension (-10dB) | ~38Hz |
| Battery Life | 30 hours (Manufacturer specified) |
| Bluetooth Codecs | AAC, SBC |
| Bluetooth Latency | SBC Video mode 48ms, AAC Video mode 128ms, SBC 112ms, AAC 176ms |
| Bluetooth Version | 5.3 |
| Built in Microphone | Yes |
| Dimensions | 15.75" x 5.91" x 8.46" (400 x 150 x 215 mm) |
| Discontinued | Yes |
| Drivers | 2x 102mm (4") woofers + 2x 20mm tweeters |
| EQ | Yes (App EQ) |
| FM Tuner | No |
| IP Rating | IP67 |
| Max Volume | 110dB |
| Output Power | 80W |
| Party Mode | Yes (Up to 50 speakers) |
| Power Bank | Yes |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | No |
| Weight | 9 lbs / 4.1 kg |
- Reviews, Comparisons and Sound Samples
- JOY‘s 3D Audio Show: B&W Zeppelin - audiophile sound quality test 🎧
- Oluv Patreon: B&W Zeppelin vs Earfun UBoom X (indoor+)
- Oluv Patreon: An evening with the “best portable speakers”?
- Joy & Oluv’Sone: Tribit Stormbox Blast vs Earfun UBoom X, a PROPER sound test 😎
- Joy & Oluv’Sone: B&O Beolit 20 vs Earfun UBoom X - everything fake?
- Joy & Oluv’Sone: 🎃🔥 UBoom X - Halloween Rock Special 🎸🤘
- JOY‘s 🎧3D🔈Audio-Show: JBL Charge 6, Xtreme 4 & Earfun UBoom X - taking sound to the top
- M1M Tech Channel: Partybox Killer? 2x Earfun UBoom X stärker als JBL Encore 2 ?
- Mateusz Cholewa: EarFun UBOOM X Deep Bass 🆚 Tribit Stormbox Blast🎶Review👌
- Mateusz Cholewa: TRIBIT StormBox LAVA vs EarFun UBOOM X
- Joy & Oluv’Sone: $600 premium Bluetooth speaker vs $115 cheapo UBoom X
- Joy & Oluv’Sone: Tribit Stormbox Blast 2 - outdoor sound test
- Joy & Oluv’Sone: Tribit Stormbox Blast 2 - indoor sound test
- Joy & Oluv’Sone: Tribit Stormbox Blast 2 vs 2 Earfun UBoom X - outdoor test
- Joy & Oluv’Sone: JBL Partybox Encore vs Earfun UBoom X: outdoors
- Joy & Oluv’Sone: JBL Partybox Encore vs Earfun UBoom X: indoors
- Joy & Oluv’Sone: Soundcore Motion Boom Plus & Earfun UBoom X - sound test
- Joy & Oluv’Sone: Earfun UBoom X vs W-King D10 - same price, same sound?
- Joy & Oluv’Sone: Best portable speakers 2025 - get the best bang for your buck $$$
- Oluv Patreon: JBL Partybox 720 - first impressions
- Oluv Patreon: Harman Kardon go+play 3 vs Earfun UBoom X
- Oluv Patreon: Earfun UBoom X vs JBL Boombox 3 - outdoor test
- Oluv Patreon: Earfun UBoom X im Vergleich zum Teufel nochmal
- Oluv Patreon: Earfun UBoom X vs JBL Boombox 3 - outdoor
- Oluv Patreon: UBoom X - desktop mode demonstration
- Oluv Patreon: Earfun UBoom X - different firmware versions
- Oluv Patreon: UBoom X - final outdoor test
- Oluv Patreon: Tribit Stormbox Blast vs Earfun UBoom X - outdoor test
- Oluv Patreon: Earfun UBoom X - listening session
- Oluv Patreon: Earfun UBoom X vs JBL Partybox 100
- Oluv Patreon: Earfun UBoom X - final sound check
- Oluv Patreon: Earfun UBoom X - teaser 3
- Oluv Patreon: Earfun UBoom X - teaser 2
- Oluv Patreon: Earfun UBoom X - teaser 1
- Oluv Patreon: Marshall Middleton II - first impressions
- Oluv Patreon: JBL Authentics 300 - listening session
- Oluv Patreon: Zealot S89 vs Yeahbox Boom Max3 - indoor listening test
- Alan Ross Reviews: Earfun Uboom X Mini Boombox bluetooth speaker, a PROPER review 😝
- JOY‘s 🎧3D🔈Audio-Show: JBL Boombox 4 vs Earfun UBoom X - sound test
- Josh’s Gadgets and More: Earfun Uboom X vs ZZA K8 sound comparison
- Joy & Oluv’Sone: J&O sEARius vs Earfun UBoom X and a bit of Bose
- Buy Used
- Head-to-Head Comparisons
- Earfun Uboom X vs Tribit Stormbox Blast
- Earfun Uboom X vs JBL Boombox 3
- Earfun Uboom X vs JBL Partybox Encore
- Earfun Uboom X vs B&O Beolit 20
- Earfun Uboom X vs B&W Zeppelin
- Earfun Uboom X vs Tribit Stormbox Lava
- Earfun Uboom X vs W-King D10
- Earfun Uboom X vs JBL Boombox 4
- Earfun Uboom X vs ZZA K8
- Earfun Uboom X vs Tribit Stormbox Blast 2
- Earfun Uboom X vs Harman Kardon Go + Play 3
- Links
Harman Kardon Onyx Studio 9: $186.99 Amazon
Pros: Auracast multi-speaker connection alongside classic stereo pairing. Harman Kardon One app with EQ. USB-C charging, up from the previous generation’s AC power brick.
Cons: Slight recessed mids, boost in the upper mids, rolled off upper treble. Not as deep bass as previous Onyx Studio speakers.
| App | Yes (Harman Kardon One app) |
|---|---|
| Bass Extension (-10dB) | 41Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Dimensions | 11.39" x 11.32" x 5.12" (289.2 x 287.5 x 130 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters |
| EQ | Yes (App EQ) |
| IP Rating | None |
| Max Volume | 101dB |
| Output Power | 50W RMS |
| Party Mode | Yes (Auracast) |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | No |
| Weight | 9.3 lbs / 4.2 kg |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Harman Kardon Onyx Studio 9 vs Altec Lansing Mix 2.0
- Harman Kardon Onyx Studio 9 vs Tronsmart Bang Max
- Harman Kardon Onyx Studio 9 vs W-King D20
- Harman Kardon Onyx Studio 9 vs Yeahbox Sonic Boom Max 3
- Harman Kardon Onyx Studio 9 vs Zealot S89
- Harman Kardon Onyx Studio 9 vs Zealot ZE21
- Harman Kardon Onyx Studio 9 vs Zealot ZE41
- Harman Kardon Onyx Studio 9 vs Altec Lansing Rockbox XL 2.0
- Harman Kardon Onyx Studio 9 vs ION Pathfinder 280
- Harman Kardon Onyx Studio 9 vs JBL Partybox Encore Essential 2
- Harman Kardon Onyx Studio 9 vs Soundcore Boom 2 Plus
- Harman Kardon Onyx Studio 9 vs Soundcore Rave Party 2
- Harman Kardon Onyx Studio 9 vs Tribit Stormbox Blast
- Harman Kardon Onyx Studio 9 vs Bugani Boost Max
- Harman Kardon Onyx Studio 9 vs Gemini GRV-650L
- Harman Kardon Onyx Studio 9 vs Harman Kardon Onyx Studio 6
- Harman Kardon Onyx Studio 9 vs Harman Kardon Onyx Studio 8
- Harman Kardon Onyx Studio 9 vs ION Pathfinder 320
- Harman Kardon Onyx Studio 9 vs JBL Partybox Encore
- Harman Kardon Onyx Studio 9 vs Skullcandy Barrel
- Harman Kardon Onyx Studio 9 vs Tronsmart Halo 200
- Harman Kardon Onyx Studio 9 vs W-King H10
- Harman Kardon Onyx Studio 9 vs Zealot S95
- Harman Kardon Onyx Studio 9 vs Harman Kardon Onyx Studio 7
- Links
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Product prices and availability were last checked August 9, 2026 at 6:57 AM UTC 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.