Short answer: the Harman Kardon Go + Play 3 for sound quality, the JBL Authentics 300 if smart-assistant integration or retro styling matter more to you. The Harman Kardon ranks #3 and the JBL ranks #44 out of 98 boombox-size speakers, and the price gap between them is $114.95.
Bass output is where these two diverge the most. The Go + Play 3 has the deepest bass of any speaker in its size class, reaching down to 35Hz, with a warm, boosted low end that reviewers say sounds notably more natural than its predecessor, the Go + Play 2. It even has hidden EQ modes accessed through button combinations for adjusting bass and treble depending on whether you’re indoors or outside. The Authentics 300 doesn’t reach nearly as deep at 45Hz, and its overall sound is described as narrow with peaky upper mids, a real step down in tonal character from the Go + Play 3.
The JBL’s real strengths are elsewhere. It’s one of the few speakers to integrate both Amazon Alexa and Google Assistant at the same time, and it pairs that with retro seventies styling, leather trim, and a Quadrex grille that the Go + Play 3 doesn’t attempt to match. It also adds Wi-Fi multi-room support and USB playback, both missing from the Harman Kardon.
Neither speaker is especially loud for the category, and battery life is a shared weak point. The Go + Play 3 is rated for 103dB max volume against the JBL’s 100dB, but reviewers note the Go + Play 3 itself measures only a little over half as loud as the higher-rated boomboxes in its class, a real limitation despite topping the sound-quality ranking. The JBL’s own reviews likewise flag it as not as loud as others. Both speakers are rated around 8 hours of battery life, on the short side for this size class, and neither carries any IP water resistance rating.
Buy the Harman Kardon Go + Play 3 if sound quality, especially bass depth, is your priority and you don’t need smart-assistant integration.
Buy the JBL Authentics 300 if you want dual Alexa and Google Assistant support, Wi-Fi multi-room playback, or its retro design language, and can accept a narrower, less bass-heavy sound.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Go + Play 3 | JBL Authentics 300 | |
|---|---|---|
| Price | $385 | $499.95 |
| Ranked | #3 of 98 in Boombox Size Portable Bluetooth Speakers | #44 of 98 in Boombox Size Portable Bluetooth Speakers |
| App | Yes (Harman Kardon One app) | Yes |
| Aux Latency | 112ms | - |
| Bass Extension (-10dB) | 35Hz | 45Hz |
| Battery Life | 8 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Built-in Microphone | Yes | Yes |
| EQ | Yes (App EQ) | Yes (App EQ) |
| IP Rating | None | None |
| Bluetooth Latency | 120ms | - |
| Maximum SPL | 103dB (measured by Alan Ross Reviews) | 100dB (measured by Alan Ross Reviews) |
| Power Input | AC Power brick | AC Power cable |
| Stereo | Yes | Partially (1 woofer) |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 10.4 lbs (4.7 kg) | 10.8 lbs (4.9 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, AAC | SBC |
| Power Bank | Yes | No |
| Party Mode | No | Yes (Wi-Fi Multi-Room) |
| USB Playback | No | Yes |
| Bluetooth Version | 5.2 | 5.3 |
| Amplifier Power | 160W RMS | 100W |
| Dimensions | 17.3” x 9.4” x 7.6” (439 x 240 x 192 mm) | 13.5” x 7.7” x 7.1” (342 x 195.6 x 180.3 mm) |
| Aux Input | Yes | No |
| Drivers | 1x 130mm (5”) subwoofer + 2x 70mm midrange drivers + 2x 20mm tweeters | 1” tweeter + 4” woofer + passive radiators |
| Digital Aux Input | No | No |
| Strap | No | No |
| Wi-Fi | - | Yes |
| MicroSD Playback | - | No |
| Voice Assistants | - | Amazon Alexa & Google Assistant (simultaneous) |
Related Speaker Comparisons
How Harman Kardon Go + Play 3 compares with other leading options:
- EarFun Uboom X vs Harman Kardon Go + Play 3
- Harman Kardon Go + Play 3 vs Tribit Stormbox Blast
- Harman Kardon Go + Play 3 vs JBL Partybox Encore 2
- Harman Kardon Go + Play 3 vs JBL Partybox Encore Essential 2
- Harman Kardon Go + Play 3 vs JBL Partybox Encore
Prices on this page were last checked October 12, 2026 at 4:13 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 Go + Play 3: $385 Amazon $385 eBay
Older model: the Harman Kardon Go + Play 2 (ranked lower, rated 3.9/5). See every Harman Kardon Go + Play generation.
Pros: Warm sound with boosted bass. Deepest bass out of any speaker in this size. Sound is more natural than the Harman Kardon Go + Play 2. An aux input, a built-in microphone, a power bank function, stereo pairing and hidden button combinations for adjusting bass and treble. Measured bass extension of 35Hz (-10dB).
Cons: Just a little over half as loud as the higher rated boomboxes. Only 8 hours of battery at medium volume. No water rating.
Setup: Use the hidden EQ modes to adjust the bass up when outside and down when inside. To adjust bass, quickly press the bluetooth and volume down buttons together, the number of light flashes tell you what mode you’re in. To adjust treble, quickly press the volume up and phone buttons at the same time, the number of yellow flashes on the light tell you what mode you are in.
Full Harman Kardon Go + Play 3 review and specifications →
| Released | Jul 2023 (3 years ago) |
|---|---|
| Amplifier Power | 160W RMS |
| App | Yes (Harman Kardon One app) |
| Aux Input | Yes |
| Aux Latency | 112ms |
| Bass Extension (-10dB) | 35Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, AAC |
| Bluetooth Latency | 120ms |
| Bluetooth Version | 5.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 17.3” x 9.4” x 7.6” (439 x 240 x 192 mm) |
| Drivers | 1x 130mm (5”) subwoofer + 2x 70mm midrange drivers + 2x 20mm tweeters |
| EQ | Yes (App EQ) |
| IP Rating | None |
| Maximum SPL | 103dB (measured by Alan Ross Reviews) |
| Omnidirectional | No |
| Party Mode | No |
| Power Bank | Yes |
| Power Input | AC Power brick |
| Stereo | Yes |
| Strap | No |
| TWS | Yes |
| USB Playback | No |
| Weight | 10.4 lbs (4.7 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Oluv Patreon: Harman Kardon go+play 3 - best sounding? More from Oluv’Sone →
- Oluv Patreon: Harman Kardon go+play 3 vs Tribit Stormbox Blast - outdoor soundtest
- Oluv Patreon: Harman Kardon go+play 3 vs JBL Xtreme 4 - first impressions
- Oluv Patreon: Harman Kardon go+play 3 vs Earfun UBoom X
- Alan Ross Reviews: Harman Kardon Go + Play 3 hidden eq modes - world has gone crazy! 🤣 More from alanrossreviews →
- Alan Ross Reviews: Harman Kardon Go+ Play 3 vs Go Play 2, the holy grail has arrived? ✔
- Alan Ross Reviews: JBL Distortion Fest vs my favorite speaker today! I wasn’t expecting this!
- Alan Ross Reviews: Minirig 2.1 or the Brane X or the Harman Kardon Go Play 3?
- Dominik Reviews: Tronsmart Fiitune X30 vs HK Go + Play 3 - No chance? - Sound Test More from Dominik Reviews →
- Dominik Reviews: Bugani Brief Pro vs Harman Kardon Go + Play 3 - HiFI Sound Comparison!
- Mateusz Cholewa: BOGASING S8 Pro Max „HiFi” 🎶🧐🆚 Harman Kardon Go Play 3 „HiFi”🔊 More from Mateusz Cholewa →
- Mateusz Cholewa: LOEWE WE Hear Pro SUPER STEREO vs HiFi Harman Kardon Go Plus Play 3
- Mateusz Cholewa: Marshall Kilburn 3 DEEP BASS 💪vs HK Go Plus Play 3 DEEP BASS❤❤❤
- Mateusz Cholewa: TEUFEL Boomster 4 vs HK Go Plus Play 3 & Opinion in Subtitles
- Mateusz Cholewa: 140W W-KING X20S vs 160W HK Go Plus Play 3
- Jagist reviews: Bugani Brief Pro Vs Harmon Kardon Go Plus Play 3!!! More from Jagistreviews →
- Jagist reviews: Bugani Boost Max Vs Harmon Kardon Go Plus Play 3!!! 😁😁😁
- Jagist reviews: W-king X20s Vs Harman Kardon Go Plus Play 3!!!
- Jagist reviews: Tronsmart Fiitune X30 Vs Harmon Kardon Go Plus Play 3!!!
- Jagist reviews: Harman Kardon Go Plus Play 3 Vs W-king H330!!!
- Head-to-Head Comparisons
- Harman Kardon Go + Play 3 vs JBL Partybox Encore 2
- Harman Kardon Go + Play 3 vs Tribit Stormbox Blast
- Harman Kardon Go + Play 3 vs EarFun Uboom X
- Harman Kardon Go + Play 3 vs JBL Partybox Encore Essential 2
- Harman Kardon Go + Play 3 vs JBL Partybox Encore
- Harman Kardon Go + Play 3 vs JBL Partybox Encore Essential
- Harman Kardon Go + Play 3 vs Harman Kardon Onyx Studio 8
- Harman Kardon Go + Play 3 vs Harman Kardon Onyx Studio 6
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JBL Authentics 300: $499.95 Amazon $499.95 eBay
Same family: the JBL Authentics 200 (smaller model, rated 3.7/5) and the JBL Authentics 500 (larger model, rated 4.1/5).
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. Measured bass extension of 45Hz (-10dB).
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 →
| Released | Sep 2023 (3 years ago) |
|---|---|
| Amplifier Power | 100W |
| App | Yes |
| Aux Input | No |
| Bass Extension (-10dB) | 45Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| 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 |
| Maximum SPL | 100dB (measured by Alan Ross Reviews) |
| MicroSD Playback | No |
| Omnidirectional | No |
| Party Mode | Yes (Wi-Fi Multi-Room) |
| Power Bank | No |
| Power Input | AC Power cable |
| Stereo | Partially (1 woofer) |
| Strap | No |
| TWS | Yes |
| USB Playback | Yes |
| Voice Assistants | Amazon Alexa & Google Assistant (simultaneous) |
| Weight | 10.8 lbs (4.9 kg) |
| Wi-Fi | 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 →
- Storytripper HD: W-King H330 vs JBL Authentics 300 More from storytripperhd →
- Head-to-Head Comparisons
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