Short answer: the Marshall Kilburn II. It ranks #39 of 93 large speakers by sound quality (rated 3.8/5) at $279 and is still sold new; the Harman Kardon Onyx Studio 4 ranks #58 (rated 3.3/5) and is discontinued, so it is only an option used.
Buy the Marshall Kilburn II. It is rated higher for sound quality and still sold new, while the Harman Kardon Onyx Studio 4 is discontinued.
There is a real battery-life gap here: the Marshall Kilburn II is rated for 20 hours, the Harman Kardon Onyx Studio 4 only 8 hours.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Marshall Kilburn II | Harman Kardon Onyx Studio 4 | |
|---|---|---|
| Price | $279.00 | $100 Discontinued |
| Ranked | #39 of 93 in Large Size Portable Bluetooth Speakers | #58 of 93 in Large Size Portable Bluetooth Speakers |
| Aux Input | Yes | Yes |
| Bass Extension (-10dB) | ~58Hz | - |
| Battery Life | 20 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| IP Rating | IPX2 | None |
| Weight | 5.5 lbs (2.49 kg) | 4.5 lbs (2.06 kg) |
| App | No | Yes (HK Connect) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| Built-in Microphone | Yes | Yes |
| EQ | No | No |
| Party Mode | No | Yes (Connect+ up to 100 speakers) |
| Power Bank | No | No |
| Power Input | USB-C | DC Barrel Connector (19V/2.1A) |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Amplifier Power | 36W | 60W |
| Dimensions | 9.6” x 6.4” x 5.5” (243 x 162 x 140 mm) | 11.4” x 11.4” x 5.1” (290 x 290 x 130 mm) |
| Drivers | 1x 4” (102mm) woofer + 2x 20mm dome tweeters | 2x 75mm woofers + 2x 20mm tweeters + 1x passive radiator |
| Maximum SPL | 102dB (Manufacturer specified) | - |
| Digital Aux Input | No | No |
| Bluetooth Version | 5.0 | 4.2 |
| Strap | Yes (built-in strap) | No |
| Frequency Response | - | 50Hz - 20kHz (Manufacturer specified) |
Related Speaker Comparisons
How Marshall Kilburn II compares with other leading options:
- Marshall Kilburn II vs Vifa Helsinki
- JBL Xtreme 5 vs Marshall Kilburn II
- Tribit Stormbox Lava vs Marshall Kilburn II
- Marshall Kilburn II vs Brane X
- Marshall Kilburn II vs Minirig 4 with subwoofer
Prices on this page were last checked October 2, 2026 at 10:18 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
Marshall Kilburn II: $279.00 Amazon eBay
Pros: 20W Class D amp + dual 8W tweeters. 20+ hour battery with quick-charge (20 min charges 3 hours of play). Rugged design with leather handle and reinforced corners, IPX2 rated. Thrives with rock music. Bluetooth 5.0 with 30ft range. Measured bass extension of ~58Hz (-10dB).
Cons: Boosted upper bass, not very detailed, not as deep bass as competitors, upper mids peak. Very low IPX2 water rating. AC charging
Full Marshall Kilburn II review and specifications →
| Amplifier Power | 36W |
|---|---|
| App | No |
| Aux Input | Yes |
| Bass Extension (-10dB) | ~58Hz |
| Battery Life | 20 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.0 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 9.6” x 6.4” x 5.5” (243 x 162 x 140 mm) |
| Drivers | 1x 4” (102mm) woofer + 2x 20mm dome tweeters |
| EQ | No |
| IP Rating | IPX2 |
| Maximum SPL | 102dB (Manufacturer specified) |
| Omnidirectional | No |
| Party Mode | No |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | Yes (built-in strap) |
| TWS | Yes |
| Weight | 5.5 lbs (2.49 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
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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
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- Harman Kardon Onyx Studio 4 vs Klipsch Detroit
- See all 38 comparisons