Harman Kardon Go + Play 3 vs JBL Authentics 300

Last updated: August 28, 2026

Short answer: the Harman Kardon Go + Play 3 for better sound quality, the JBL Authentics 300 for the lower price. The Harman Kardon Go + Play 3 ranks #3 of 73 boombox speakers at $385. The JBL Authentics 300 ranks #30 at $299.95, $85.05 cheaper.

What the Harman Kardon Go + Play 3 offers: Warm sound with boosted bass. Deepest bass out of any speaker in this size. Sound is more natural than the Go + Play2. Watch for: Just a little over half as loud as the higher rated boomboxes. Only 8 hours of battery at medium volume. 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 Go + Play 3 if sound quality matters more than the price. Buy the JBL Authentics 300 if the price matters more than sound quality.

Buy the Harman Kardon Go + Play 3 at Amazon ($385) →Buy the JBL Authentics 300 at Amazon ($299.95) →

Harman Kardon Go + Play 3 vs JBL Authentics 300

Specifications Side By Side

Harman Kardon Go + Play 3 JBL Authentics 300
Price$385$299.95
Ranked#3 of 73 in Boombox Size Portable Bluetooth Speakers#30 of 73 in Boombox Size Portable Bluetooth Speakers
AppYes (Harman Kardon One app)Yes
Aux Latency112ms-
Bass Extension (-10dB)35Hz45Hz
Battery Life8 hours (Manufacturer specified)8 hours (Manufacturer specified)
Built in MicrophoneYesYes
EQYes (App EQ)Yes (App EQ)
IP RatingNoneNone
Bluetooth Latency120ms-
Max Volume103dB100dB
Power InputAC Power brickAC Power cable
StereoYesPartially (1 woofer)
OmnidirectionalNoNo
TWSYesYes
Weight10.4 lbs / 4.7 kg10.8 lbs / 4.9 kg
Bluetooth CodecsSBC, AACSBC
Power BankYesNo
Party ModeNoYes (Wi-Fi Multi-Room)
USB PlaybackNoYes
Bluetooth Version5.2-
Output Power160W RMS100W
Dimensions17.3" 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 InputYesNo
Drivers1x 130mm (5") subwoofer + 2x 70mm midrange drivers + 2x 20mm tweeters1" tweeter + 4" woofer + passive radiators
Digital Aux InputNoNo
Wifi-Yes
MicroSD Playback-No
Buy the Harman Kardon Go + Play 3 at Amazon ($385) →Buy the JBL Authentics 300 at Amazon ($299.95) →

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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.

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The Two Speakers In Full

Harman Kardon Go + Play 3: $385 Amazon eBay

Harman Kardon Go + Play 3 ranking card

Pros: Warm sound with boosted bass. Deepest bass out of any speaker in this size. Sound is more natural than the Go + Play2.

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 →

AppYes (Harman Kardon One app)
Aux InputYes
Aux Latency112ms
Bass Extension (-10dB)35Hz
Battery Life8 hours (Manufacturer specified)
Bluetooth CodecsSBC, AAC
Bluetooth Latency120ms
Bluetooth Version5.2
Built in MicrophoneYes
Digital Aux InputNo
Dimensions17.3" x 9.4" x 7.6" (439 x 240 x 192 mm)
Drivers1x 130mm (5") subwoofer + 2x 70mm midrange drivers + 2x 20mm tweeters
EQYes (App EQ)
IP RatingNone
Max Volume103dB
OmnidirectionalNo
Output Power160W RMS
Party ModeNo
Power BankYes
Power InputAC Power brick
StereoYes
TWSYes
USB PlaybackNo
Weight10.4 lbs / 4.7 kg
Check current price at Amazon ($385) →Search eBay for Harman Kardon Go + Play 3 →

JBL Authentics 300: $299.95 Amazon eBay

JBL Authentics 300 ranking card

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 →

AppYes
Aux InputNo
Bass Extension (-10dB)45Hz
Battery Life8 hours (Manufacturer specified)
Bluetooth CodecsSBC
Built in MicrophoneYes
Digital Aux InputNo
Dimensions13.5" x 7.7" x 7.1" (342 x 195.6 x 180.3 mm)
Drivers1" tweeter + 4" woofer + passive radiators
EQYes (App EQ)
IP RatingNone
Max Volume100dB
MicroSD PlaybackNo
OmnidirectionalNo
Output Power100W
Party ModeYes (Wi-Fi Multi-Room)
Power BankNo
Power InputAC Power cable
StereoPartially (1 woofer)
TWSYes
USB PlaybackYes
Weight10.8 lbs / 4.9 kg
WifiYes
Check current price at Amazon ($299.95) →Search eBay for JBL Authentics 300 →