Short answer: the Harman Kardon Onyx Studio 8. It ranks #10 of 73 boombox speakers by sound quality at $159.99; the JBL Authentics 300 ranks #30 and costs $299.95, so there is little reason to consider the other one.
What the Harman Kardon Onyx Studio 8 offers: Warm sound with boosted bass. Watch for: Not as loud as others. No water rating.
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 8. It ranks higher for sound quality than the JBL Authentics 300 and costs less, so there is no real case for the other one.
Specifications Side By Side
| Harman Kardon Onyx Studio 8 | JBL Authentics 300 | |
|---|---|---|
| Price | $159.99 | $299.95 |
| Ranked | #10 of 73 in Boombox Size Portable Bluetooth Speakers | #30 of 73 in Boombox Size Portable Bluetooth Speakers |
| Aux Input | Yes | No |
| Aux Latency | 42ms | - |
| Bass Extension (-10dB) | 35Hz | 45Hz |
| Battery Life | 8 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Built in Microphone | Yes | Yes |
| IP Rating | None | None |
| Bluetooth Latency | 175ms | - |
| Max Volume | 96dB | 100dB |
| Power Input | DC Barrel Connector (19V/2.1A) | AC Power cable |
| Stereo | Yes | Partially (1 woofer) |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 7.3 lbs / 3.3 kg | 10.8 lbs / 4.9 kg |
| App | Yes (Harman Kardon One app) | Yes |
| Bluetooth Codecs | SBC | SBC |
| Power Bank | No | No |
| EQ | Yes (App EQ) | Yes (App EQ) |
| Party Mode | No | Yes (Wi-Fi Multi-Room) |
| USB Playback | No | Yes |
| Bluetooth Version | 5.2 | - |
| Output Power | 50W RMS | 100W |
| Dimensions | 10.6" x 11.9" x 6.3" (268 x 302.5 x 159.5 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
Other pairings from the same speaker class worth checking:
- JBL Partybox Encore Essential vs Harman Kardon Onyx Studio 6
- JBL Partybox Encore 2 vs Harman Kardon Onyx Studio 6
- Turtlebox vs Harman Kardon Onyx Studio 6
- Harman Kardon Onyx Studio 8 vs Tribit Stormbox Blast 2
- Harman Kardon Onyx Studio 8 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 8: $159.99 Amazon eBay
Pros: Warm sound with boosted bass.
Cons: Not as loud as others. No water rating.
Full Harman Kardon Onyx Studio 8 review and specifications →
| App | Yes (Harman Kardon One app) |
|---|---|
| Aux Input | Yes |
| Aux Latency | 42ms |
| Bass Extension (-10dB) | 35Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Latency | 175ms |
| Bluetooth Version | 5.2 |
| Built in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 10.6" x 11.9" x 6.3" (268 x 302.5 x 159.5 mm) |
| Drivers | 2x 75mm woofers + 2x 20mm tweeters |
| EQ | Yes (App EQ) |
| IP Rating | None |
| Max Volume | 96dB |
| Omnidirectional | No |
| Output Power | 50W RMS |
| Party Mode | No |
| Power Bank | No |
| Power Input | DC Barrel Connector (19V/2.1A) |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | No |
| Weight | 7.3 lbs / 3.3 kg |
- Links
- Reviews, Comparisons and Sound Samples
- Alan Ross Reviews: Harman Kardon Onyx Studio 8 review - part 2 of 3 More from alanrossreviews →
- Alan Ross Reviews: Onyx Studio 8 vs HK Onyx 6, Xtreme 3, PartyBox Encore, Go+ Play, Bag of Riddim! part 3 of 3
- Alan Ross Reviews: Dead room vs Live room - Onyx studio 8 self tuning test! part 1 of 3
- Alan Ross Reviews: Ultimate HK Onyx Studio speaker review and comparison! 8 speakers!
- Reddit Search for Harman Kardon Onyx Studio 8 Review
- Head-to-Head Comparisons
- Harman Kardon Onyx Studio 8 vs Harman Kardon Onyx Studio 6
- Harman Kardon Onyx Studio 8 vs Vifa Copenhagen 2.0
- Harman Kardon Onyx Studio 8 vs Harman Kardon Onyx Studio 7
- Harman Kardon Onyx Studio 8 vs Aiwa Exos-9
- Harman Kardon Onyx Studio 8 vs Harman Kardon Onyx Studio 9
- Harman Kardon Onyx Studio 8 vs JBL Partybox Encore Essential
- Harman Kardon Onyx Studio 8 vs JBL Partybox Encore
- Harman Kardon Onyx Studio 8 vs Zealot ZE41
- See all 44 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