Short answer: the Zealot ZE21. It ranks #15 of 73 boombox speakers by sound quality at $247.41; the JBL Authentics 300 ranks #30 and costs $299.95, so there is little reason to consider the other one.
What the Zealot ZE21 offers: Great value for the bass performance, play time and max volume in the boombox class, though the Zealot ZE41 now beats it out. Watch for: A little rolled off up top and not that balanced through the rest of the range. Clarity isn’t as good as better speakers. Bass EQ is bloated and muddy sounding
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 Zealot ZE21. It ranks higher for sound quality than the JBL Authentics 300 and costs less, so there is no real case for the other one.
There is a real battery-life gap here: the Zealot ZE21 is rated for 40 hours, the JBL Authentics 300 only 8 hours.
If water resistance matters to you, the Zealot ZE21 at IPX6 (powerful water jets) holds up far better than the JBL Authentics 300 at no water resistance.
Specifications Side By Side
| Zealot ZE21 | JBL Authentics 300 | |
|---|---|---|
| Price | $247.41 | $299.95 |
| Ranked | #15 of 73 in Boombox Size Portable Bluetooth Speakers | #30 of 73 in Boombox Size Portable Bluetooth Speakers |
| App | No | Yes |
| Aux Input | Yes | No |
| Bass Extension (-10dB) | 36Hz | 45Hz |
| Battery Life | 40 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| EQ | Yes (multiple modes) | Yes (App EQ) |
| IP Rating | IPX6 | None |
| MicroSD Playback | Yes | No |
| Party Mode | Yes (PartyAdd up to 100 speakers) | Yes (Wi-Fi Multi-Room) |
| Power Input | USB-C | AC Power cable |
| Stereo | Yes | Partially (1 woofer) |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 20.4 lbs / 9.27 kg | 10.8 lbs / 4.9 kg |
| Bluetooth Codecs | SBC | SBC |
| Power Bank | Yes (USB-A + USB-C) | No |
| USB Playback | Yes | Yes |
| Built in Microphone | No | Yes |
| Output Power | 250W | 100W |
| Dimensions | 16.7" x 10.3" x 14.3" (424 x 262 x 363 mm) | 13.5" x 7.7" x 7.1" (342 x 195.6 x 180.3 mm) |
| Drivers | 130W subwoofer + 2x 50mm woofers + passive radiators | 1" tweeter + 4" woofer + passive radiators |
| Max Volume | 116dB | 100dB |
| Digital Aux Input | No | No |
| Wifi | - | Yes |
Related Speaker Comparisons
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- Tribit Stormbox Blast 2 vs Zealot ZE21
- Zealot ZE21 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.
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The Two Speakers In Full
Zealot ZE21: $247.41 Amazon Aliexpress eBay
Pros: Great value for the bass performance, play time and max volume in the boombox class, though the Zealot ZE41 now beats it out.
Cons: A little rolled off up top and not that balanced through the rest of the range. Clarity isn’t as good as better speakers. Bass EQ is bloated and muddy sounding
Full Zealot ZE21 review and specifications →
| App | No |
|---|---|
| Aux Input | Yes |
| Bass Extension (-10dB) | 36Hz |
| Battery Life | 40 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Built in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 16.7" x 10.3" x 14.3" (424 x 262 x 363 mm) |
| Drivers | 130W subwoofer + 2x 50mm woofers + passive radiators |
| EQ | Yes (multiple modes) |
| IP Rating | IPX6 |
| Max Volume | 116dB |
| MicroSD Playback | Yes |
| Omnidirectional | No |
| Output Power | 250W |
| Party Mode | Yes (PartyAdd up to 100 speakers) |
| Power Bank | Yes (USB-A + USB-C) |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 20.4 lbs / 9.27 kg |
- Links
- Reviews, Comparisons and Sound Samples
- Jagist reviews: Jbl Boombox 4 Vs Zealot Ze21!!! More from Jagistreviews →
- Jagist reviews: Zealot Ze21 Vs Tribit Stormbox Blast 2!!!
- Techder Audios: JBL Boombox 4 VS Zealot ZE21 BATTLE OF THE BOOMBOXES! More from techderaudios →
- Jay’s Straight Up Reviews & More: Zealot ZE21 vs JBL Boombox 3 Tailgater Special @20ft. The Budget Beast Against the OG Boombox More from JaysStraightUpReviews →
- Reddit Search for Zealot ZE21 Review
- Head-to-Head Comparisons
- Zealot ZE21 vs Zealot ZE41
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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
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