Short answer: the Harman Kardon Onyx Studio 4 for bass, the Ultimate Ears Megablast for loudness and Alexa. The Megablast is the loudest in the UE lineup at 93dB and 40% louder than the Megaboom, with Alexa over Wi-Fi and Bluetooth, but its bass is not very deep. The Onyx Studio 4 has the deeper, more balanced sound, at the cost of loudness and an 8 hour battery at medium volume, at $100 versus $240.
Buy the Harman Kardon Onyx Studio 4 only if you find one used in good condition; both are discontinued, and it is the better rated of the two. For a new speaker, start with the Tribit Stormbox Lava instead.
Battery life favors the Ultimate Ears Megablast: rated for 16 hours against 8 hours for the Harman Kardon Onyx Studio 4.
Water resistance is not close: the Ultimate Ears Megablast is rated at IPX7 (brief submersion), well ahead of the Harman Kardon Onyx Studio 4 at no water resistance.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Onyx Studio 4 | Ultimate Ears Megablast | |
|---|---|---|
| Price | $100 Discontinued | $240 Discontinued |
| Ranked | #61 of 97 in Large Size Portable Bluetooth Speakers | #80 of 97 in Large Size Portable Bluetooth Speakers |
| App | Yes (HK Connect) | No |
| Aux Input | Yes | Yes |
| Battery Life | 8 hours (Manufacturer specified) | 16 hours (Manufacturer specified) |
| EQ | No | No |
| IP Rating | None | IPX7 |
| Party Mode | Yes (Connect+ up to 100 speakers) | No |
| Power Bank | No | No |
| TWS | Yes | Yes |
| Weight | 4.5 lbs (2.06 kg) | 2.4 lbs (1.1 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| Built-in Microphone | Yes | Yes |
| Power Input | DC Barrel Connector (19V/2.1A) | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| Bluetooth Version | 4.2 | 4.2 |
| Drivers | 2x 75mm woofers + 2x 20mm tweeters + 1x passive radiator | 2x 55mm fullrange, 2x 25mm tweeters |
| Dimensions | 11.4” x 11.4” x 5.1” (290 x 290 x 130 mm) | 9.3” x 3.5” (236.2 x 88.9 mm) (height x diameter) |
| Frequency Response | 50Hz - 20kHz (Manufacturer specified) | 60Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | 60W | - |
| Digital Aux Input | No | No |
| Strap | No | - |
| Bass Extension (-10dB) | - | 64Hz |
| Wi-Fi | - | Yes |
| Voice Assistants | - | Amazon Alexa |
Related Speaker Comparisons
How Harman Kardon Onyx Studio 4 compares with other leading options:
- JBL Xtreme 5 vs Harman Kardon Onyx Studio 4
- Tribit Stormbox Lava vs Harman Kardon Onyx Studio 4
- Soundcore Boom 2 vs Harman Kardon Onyx Studio 4
- Marshall Stockwell II vs Harman Kardon Onyx Studio 4
- Harman Kardon Citation 200 vs Harman Kardon Onyx Studio 4
Prices on this page were last checked October 3, 2026 at 10:26 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 Onyx Studio 4: $100 Discontinued eBay
Newer model: the Harman Kardon Onyx Studio 9, rated 4.1/5.
Pros: Balanced sound quality with deep resonant bass and crisp treble, large dynamic range. Multi-host Bluetooth connectivity for 2 phones, daisy chaining up to 100 speakers. Elegant modern design with smooth curves and premium materials.
Cons: 8 hour battery at medium volume. Not at loud as others. Not as deep of bass as the newer Onyx. External AC power brick for charging. Discontinued.
Full Harman Kardon Onyx Studio 4 review and specifications →
| Amplifier Power | 60W |
|---|---|
| App | Yes (HK Connect) |
| Aux Input | Yes |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 4.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 11.4” x 11.4” x 5.1” (290 x 290 x 130 mm) |
| Drivers | 2x 75mm woofers + 2x 20mm tweeters + 1x passive radiator |
| EQ | No |
| Frequency Response | 50Hz - 20kHz (Manufacturer specified) |
| IP Rating | None |
| Omnidirectional | No |
| Party Mode | Yes (Connect+ up to 100 speakers) |
| Power Bank | No |
| Power Input | DC Barrel Connector (19V/2.1A) |
| Stereo | Yes |
| Strap | No |
| TWS | Yes |
| Weight | 4.5 lbs (2.06 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Harman Kardon Onyx Studio 4 vs Zealot S97
- Harman Kardon Onyx Studio 4 vs Tronsmart Halo 100
- Harman Kardon Onyx Studio 4 vs JBL Xtreme 2
- Harman Kardon Onyx Studio 4 vs JBL Xtreme
- Harman Kardon Onyx Studio 4 vs Doss Soundbox XL
- Harman Kardon Onyx Studio 4 vs W-King D8
- Harman Kardon Onyx Studio 4 vs Sony SRS-XB43
- Harman Kardon Onyx Studio 4 vs Klipsch Detroit
- See all 38 comparisons
Ultimate Ears Megablast: $240 Discontinued eBay
Pros: Alexa integration (Wi-Fi + Bluetooth). 93dB loudest in UE lineup, 40% louder than Megaboom. IP67 waterproof and drop-proof. 16 hour battery. Party mode connects up to 8 speakers. Can use while charging to keep Alexa on 24/7. Measured bass extension of 64Hz (-10dB).
Cons: Bass is not very deep compared to the competition. Discontinued.
Full Ultimate Ears Megablast review and specifications →
| App | No |
|---|---|
| Aux Input | Yes |
| Bass Extension (-10dB) | 64Hz |
| Battery Life | 16 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 4.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 9.3” x 3.5” (236.2 x 88.9 mm) (height x diameter) |
| Drivers | 2x 55mm fullrange, 2x 25mm tweeters |
| EQ | No |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) |
| IP Rating | IPX7 |
| Omnidirectional | No |
| Party Mode | No |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| Voice Assistants | Amazon Alexa |
| Weight | 2.4 lbs (1.1 kg) |
| Wi-Fi | Yes |
- Reviews, Comparisons and Sound Samples
- No independent measurement review is linked for this model; it is ranked from hands-on listening and comparison against similarly priced speakers.
- Head-to-Head Comparisons
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