Short answer: the Harman Kardon Onyx Studio 6. It ranks #11 of 73 boombox speakers by sound quality at $130; the JBL Authentics 300 ranks #30 and costs $299.95, which makes this an easy call rather than a real tradeoff.
What the Harman Kardon Onyx Studio 6 offers: Warm sound with boosted bass. Oluv liked it slightly better than the newer Onyx 7. Watch for: 8 hour battery at medium volume. Not at loud as others.
What the JBL Authentics 300 offers: Integrates both Amazon Alexa and Google Assistant simultaneously (rare for smart speakers). Retro seventies design with leather and Quadrex grille. 100-watt amp, carries well with leather-trimmed handle. Rechargeable battery rated ~8 hours. Watch for: Narrow sounding, bass not as deep as others. Peaky upper mids. No TWS. No IP rating. Not as loud as others. Not much battery life.
Buy the Harman Kardon Onyx Studio 6. It ranks higher for sound quality than the JBL Authentics 300 and costs less, which settles it without a real tradeoff to make.
If water resistance matters to you, the Harman Kardon Onyx Studio 6 at IPX7 (brief submersion) holds up far better than the JBL Authentics 300 at no water resistance.
Specifications Side By Side
| Harman Kardon Onyx Studio 6 | JBL Authentics 300 | |
|---|---|---|
| Price | $130 | $299.95 |
| Ranked | #11 of 73 in Boombox Size Portable Bluetooth Speakers | #30 of 73 in Boombox Size Portable Bluetooth Speakers |
| Aux Input | Yes | No |
| Bass Extension (-10dB) | 37Hz | 45Hz |
| Battery Life | 8 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Built in Microphone | Yes | Yes |
| IP Rating | IPX7 | None |
| Bluetooth Latency | 180ms | - |
| Max Volume | 96dB | 100dB |
| Party Mode | Yes (Wireless Dual Sound) | Yes (Wi-Fi Multi-Room) |
| Power Input | DC Barrel Connector (19V/2A) | AC Power cable |
| Stereo | Yes | Partially (1 woofer) |
| Omnidirectional | No | No |
| TWS | Yes (see https://www.reddit.com/r/Bluetooth_Speakers/comments/w339x5/how_to_harman_kardon_onyx_studio_5_6_dual_sound/) | Yes |
| Weight | 6.5 lbs / 2.94 kg | 10.8 lbs / 4.9 kg |
| Bluetooth Codecs | SBC | SBC |
| App | No | Yes |
| EQ | No | Yes (App EQ) |
| Power Bank | No | No |
| USB Playback | No | Yes |
| Bluetooth Version | 4.2 | - |
| Output Power | 50W RMS | 100W |
| Dimensions | 5" x 11.5" x 11.2" (128 x 291 x 284 mm) | 13.5" x 7.7" x 7.1" (342 x 195.6 x 180.3 mm) |
| Drivers | 2x 75mm woofers + 2x 20mm tweeters | 1" tweeter + 4" woofer + passive radiators |
| Digital Aux Input | No | No |
| Wifi | - | Yes |
| MicroSD Playback | - | No |
Related Speaker Comparisons
A few more comparisons worth a look in the same class:
- Harman Kardon Onyx Studio 7 vs Soundcore Motion Boom+
- Harman Kardon Onyx Studio 7 vs W-King X10-1
- Harman Kardon Onyx Studio 7 vs W-King T11
- Harman Kardon Onyx Studio 6 vs Tribit Stormbox Blast 2
- Harman Kardon Onyx Studio 6 vs JBL Partybox On the Go
Prices on this page were last checked August 27, 2026 at 10:09 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.
As an eBay Partner, we may be compensated if you make a purchase.
The Two Speakers In Full
Harman Kardon Onyx Studio 6: $130 Amazon eBay
Pros: Warm sound with boosted bass. Oluv liked it slightly better than the newer Onyx 7.
Cons: 8 hour battery at medium volume. Not at loud as others.
Full Harman Kardon Onyx Studio 6 review and specifications →
| App | No |
|---|---|
| Aux Input | Yes |
| Bass Extension (-10dB) | 37Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Latency | 180ms |
| Bluetooth Version | 4.2 |
| Built in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 5" x 11.5" x 11.2" (128 x 291 x 284 mm) |
| Drivers | 2x 75mm woofers + 2x 20mm tweeters |
| EQ | No |
| IP Rating | IPX7 |
| Max Volume | 96dB |
| Omnidirectional | No |
| Output Power | 50W RMS |
| Party Mode | Yes (Wireless Dual Sound) |
| Power Bank | No |
| Power Input | DC Barrel Connector (19V/2A) |
| Stereo | Yes |
| TWS | Yes (see https://www.reddit.com/r/Bluetooth_Speakers/comments/w339x5/how_to_harman_kardon_onyx_studio_5_6_dual_sound/) |
| USB Playback | No |
| Weight | 6.5 lbs / 2.94 kg |
- Links
- Reviews, Comparisons and Sound Samples
- Alan Ross Reviews: Onyx Studio 7 vs Onyx Studio 6 - massive deep bass battle 😁 More from alanrossreviews →
- That Speaker Guy: Harman Kardon Onyx Studio 6 vs Devialet Mania
- Ezekielo: Citation 200 vs Onyx Studio 6 vs Bose Portable Speaker Sound Comparison
- Alan Ross Reviews: Harman Kardon Go+ Play 2 mini or Onyx Studio 6 - best speaker for bass?
- Alan Ross Reviews: Ultimate HK Onyx Studio speaker review and comparison! 8 speakers!
- Reddit Search for Harman Kardon Onyx Studio 6 Review
- Head-to-Head Comparisons
- Harman Kardon Onyx Studio 6 vs Harman Kardon Onyx Studio 8
- Harman Kardon Onyx Studio 6 vs Harman Kardon Onyx Studio 7
- Harman Kardon Onyx Studio 6 vs Harman Kardon Onyx Studio 9
- Harman Kardon Onyx Studio 6 vs Vifa Copenhagen 2.0
- Harman Kardon Onyx Studio 6 vs Zealot ZE41
- Harman Kardon Onyx Studio 6 vs JBL Partybox Encore Essential
- Harman Kardon Onyx Studio 6 vs Zealot ZE21
- Harman Kardon Onyx Studio 6 vs JBL Partybox Encore
- See all 45 comparisons
JBL Authentics 300: $299.95 Amazon eBay
Pros: Integrates both Amazon Alexa and Google Assistant simultaneously (rare for smart speakers). Retro seventies design with leather and Quadrex grille. 100-watt amp, carries well with leather-trimmed handle. Rechargeable battery rated ~8 hours.
Cons: Narrow sounding, bass not as deep as others. Peaky upper mids. No TWS. No IP rating. Not as loud as others. Not much battery life.
Full JBL Authentics 300 review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Bass Extension (-10dB) | 45Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Built in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 13.5" x 7.7" x 7.1" (342 x 195.6 x 180.3 mm) |
| Drivers | 1" tweeter + 4" woofer + passive radiators |
| EQ | Yes (App EQ) |
| IP Rating | None |
| Max Volume | 100dB |
| MicroSD Playback | No |
| Omnidirectional | No |
| Output Power | 100W |
| Party Mode | Yes (Wi-Fi Multi-Room) |
| Power Bank | No |
| Power Input | AC Power cable |
| Stereo | Partially (1 woofer) |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 10.8 lbs / 4.9 kg |
| Wifi | Yes |
- Links
- Reviews, Comparisons and Sound Samples
- JOY‘s 🎧3D🔈Audio-Show: JBL Authentics 300 - sound quality test More from Oluv’Sone →
- Oluv Patreon: JBL Authentics 300 - update
- Oluv Patreon: JBL Authentics 300 - listening session
- Alan Ross Reviews: Not quite! JBL Authentics 300 review and sound test vs Boombox 3, Encore and Stormbox Blast More from alanrossreviews →
- Reddit Search for JBL Authentics 300 Review
- Head-to-Head Comparisons
- JBL Authentics 300 vs JBL Boombox 2
- JBL Authentics 300 vs B&O Beolit 20
- JBL Authentics 300 vs W-King X20
- JBL Authentics 300 vs Teufel Boomster 2021
- JBL Authentics 300 vs W-King D20
- JBL Authentics 300 vs Soundcore Boom 2 Plus
- JBL Authentics 300 vs Zealot ZE01
- JBL Authentics 300 vs W-King T11
- See all 50 comparisons