Short answer: the JBL Boombox 4 is the output-first option, while the Zealot ZE51 is a less expensive route to a cleaner, wider Zealot sound. ZE51 improves on the ZE41 with lower distortion at high level and a broader stereo presentation.
It is still a large, heavy boombox and does not deliver dedicated hi-fi-speaker clarity. Its sibling retains the advantage in raw bass depth and price.
Boombox 4 has exceptional output capability, but it is expensive for the category. Its important advantage over Boombox 3 is seven EQ bands instead of three, so its best result depends substantially on applying a thoughtful EQ such as Oluv’s.
Buy the Zealot ZE51 if a cleaner Zealot presentation and wider stereo image matter more than ultimate loudness.
Buy the JBL Boombox 4 if maximum output and a flexible seven-band EQ are worth the premium.
If battery life is a priority, the JBL Boombox 4 is rated for 28 hours versus 4 hours for the Zealot ZE51.
There is a real gap in water resistance: the JBL Boombox 4 at IP68 (extended submersion) against the Zealot ZE51, which has IPX5 (water jets).
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Zealot ZE51 | JBL Boombox 4 | |
|---|---|---|
| Price | $296.39 after coupon | $549.95 |
| Ranked | #16 of 99 in Boombox Size Portable Bluetooth Speakers | #20 of 99 in Boombox Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | Yes | No |
| Battery Capacity | 48000mAh (12x4000mAh) | - |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 5.4 |
| Dimensions | 22.1” x 9.4” x 13” (562 x 238 x 331 mm) | 20.1” x 10.2” x 8.3” (510 x 260 x 210 mm) |
| EQ | Yes (Hi-Res, 3D Surround, Extra Bass, Vocal and other sound modes) | Yes (7 band) |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) | - |
| IP Rating | IPX5 | IP68 |
| Microphone Input | Yes (Karaoke mode) | No |
| MicroSD Playback | Yes | No |
| Amplifier Power | 250W | 210W AC / 200W battery |
| Power Bank | Yes (USB-A + USB-C) | Yes (USB-C, up to 30W) |
| Power Input | Type-C | AC Power cord |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | No |
| Weight | 26 lbs (11.81 kg) | 13.2 lbs (5.98 kg) |
| Digital Aux Input | No | Yes (USB-C) |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) | SBC, LC3, AAC |
| Drivers | 1x 133mm + 2x 93mm + 2x 45mm | 2x 123mm woofers + 2x 20mm tweeters with passive radiators |
| Battery Life | 4 hours (Manufacturer specified) | 28 hours (Manufacturer specified) |
| Strap | Yes (strap) | No |
| Bass Extension (-10dB) | - | 41Hz |
| Bluetooth Latency | - | AAC 144ms, SBC 48ms |
| Maximum SPL | - | 115dB (measured by Alan Ross Reviews) |
| Party Mode | - | Yes (Auracast) |
| Removable Battery | - | Yes |
| Built-in Microphone | - | No |
| FM Tuner | - | No |
Watch Them Compared
Videos and reviews that test both speakers side by side.
Related Speaker Comparisons
More worthwhile head-to-heads for Zealot ZE51:
- Zealot ZE51 vs EarFun Uboom X
- Zealot ZE51 vs Tribit Stormbox Blast
- Zealot ZE51 vs Harman Kardon Go + Play 3
- Zealot ZE51 vs JBL Partybox Encore 2
- JBL PartyBox On-The-Go 2 Plus vs Zealot ZE51
Prices on this page were last checked October 14, 2026 at 2:38 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
Zealot ZE51: $296.39 after coupon Amazon $296.39 AliExpress $235.33 eBay
Pros: Cleaner sound and a wider stereo soundstage than the Zealot ZE41, with less distortion at high volume for better instrumental detail and clarity.
Cons: The Zealot ZE41 still wins on raw bass depth and price. Large and heavy like the rest of the boombox class, and clarity still isn’t up to dedicated hi-fi speakers.
Full Zealot ZE51 review and specifications →
| Released | Mar 2026 (7 months ago) |
|---|---|
| Amplifier Power | 250W |
| App | Yes |
| Aux Input | Yes |
| Battery Capacity | 48000mAh (12x4000mAh) |
| Battery Life | 4 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 22.1” x 9.4” x 13” (562 x 238 x 331 mm) |
| Drivers | 1x 133mm + 2x 93mm + 2x 45mm |
| EQ | Yes (Hi-Res, 3D Surround, Extra Bass, Vocal and other sound modes) |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) |
| IP Rating | IPX5 |
| MicroSD Playback | Yes |
| Microphone Input | Yes (Karaoke mode) |
| Omnidirectional | No |
| Power Bank | Yes (USB-A + USB-C) |
| Power Input | Type-C |
| Stereo | Yes |
| Strap | Yes (strap) |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 26 lbs (11.81 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- J_Strat Battles: Zealot ZE51 short hz test video
- J_Strat Battles: ZEALOT ZE51 VS JBL BOOMBOX 4 (OLD FIRMWARE VERSION) 🧨🧨🧨
- J_Strat Battles: Zealot ZE51 VS ZE21
- J_Strat Battles: ZEALOT ZE51 VS W-KING X20 🥳🥳
- J_Strat Battles: Zealot ZE51 vs ZE21 bass boost/vocal eq battle 💪🏻😎
- J_Strat Battles: Zealot ZE51 vs PT11 😎😎😎
- Head-to-Head Comparisons
- Zealot ZE51 vs Zealot ZE41
- Zealot ZE51 vs Harman Kardon Onyx Studio 9
- Zealot ZE51 vs Zealot ZE21
- Zealot ZE51 vs Harman Kardon Onyx Studio 7
- Zealot ZE51 vs Zealot S89
- Zealot ZE51 vs Harman Kardon Onyx Studio 6
- Zealot ZE51 vs Harman Kardon Onyx Studio 8
- Zealot ZE51 vs Yeahbox Sonic Boom Ultra
- See all 87 comparisons
JBL Boombox 4: $549.95 Amazon $549.95 B&H Photo Video $549.95 eBay
Older models: the JBL Boombox 3 Wifi (ranked lower, rated 3.8/5), the JBL Boombox 3 (ranked lower, rated 3.8/5), the JBL Boombox 2 (ranked lower, rated 3.5/5) and the JBL Boombox (ranked lower, rated 2.9/5). See every JBL Boombox generation.
Pros: Pretty insane output capability for the size. IP68 protection and Auracast pairing with other current JBL speakers. Measured bass extension of 41Hz (-10dB).
Cons: Pretty overpriced for the category. Better than the JBL Boombox 3 mostly because there are more 7 EQ bands instead of just 3 and it can be better tuned. Try Oluv’s EQ for it. Out of the box sounds worse than the JBL Boombox 3. No Aux input.
Full JBL Boombox 4 review and specifications →
| Released | Jul 2025 (1 year ago) |
|---|---|
| Amplifier Power | 210W AC / 200W battery |
| App | Yes |
| Aux Input | No |
| Bass Extension (-10dB) | 41Hz |
| Battery Life | 28 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, LC3, AAC |
| Bluetooth Latency | AAC 144ms, SBC 48ms |
| Bluetooth Version | 5.4 |
| Built-in Microphone | No |
| Digital Aux Input | Yes (USB-C) |
| Dimensions | 20.1” x 10.2” x 8.3” (510 x 260 x 210 mm) |
| Drivers | 2x 123mm woofers + 2x 20mm tweeters with passive radiators |
| EQ | Yes (7 band) |
| FM Tuner | No |
| IP Rating | IP68 |
| Maximum SPL | 115dB (measured by Alan Ross Reviews) |
| MicroSD Playback | No |
| Microphone Input | No |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Bank | Yes (USB-C, up to 30W) |
| Power Input | AC Power cord |
| Removable Battery | Yes |
| Stereo | Yes |
| Strap | No |
| TWS | Yes |
| USB Playback | No |
| Weight | 13.2 lbs (5.98 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- JOY‘s 🎧3D🔈Audio-Show: JBL Boombox 4 - finally a real BOOMbox from JBL 👏 More from Oluv’Sone →
- JOY‘s 🎧3D🔈Audio-Show: JBL Boombox 4 vs Boombox 3 - old one sounding better? 🤔
- JOY‘s 🎧3D🔈Audio-Show: JBL Boombox 4 vs Earfun UBoom X - sound test
- JOY‘s 🎧3D🔈Audio-Show: JBL Boombox 4 vs Boombox 3 - any improvement?
- JOY‘s 🎧3D🔈Audio-Show: JBL Boombox 4 vs Partybox Encore 2 - outdoor loudness & basstest
- Alan Ross Reviews: JBL Boombox 4 distortion fest bonanza! how bad can it be lol 🤣 More from alanrossreviews →
- Alan Ross Reviews: JBL Boombox 4 HUMILIATES Brane X?! Ultimate Bass Battle!
- Alan Ross Reviews: JBL Boombox 4 Compared to Boombox 3 & 3 WiFi – Worth the Upgrade?
- Alan Ross Reviews: JBL Distortion Fest vs my favorite speaker today! I wasn’t expecting this!
- M1MTechChannel: JBL BOOMBOX 4 - Einfach komplett GEISTESKRANK More from M1MTechChannel →
- M1MTechChannel: Welche JBL Partybox ist die BESTE ? Alle Partyboxen im Vergleich | 2026
- Dominik Reviews: Zealot S89 vs JBL Boombox 4 - JBL Alternative? Sound Test More from Dominik Reviews →
- Techder Audios: JBL Boombox 4 VS Zealot ZE21 BATTLE OF THE BOOMBOXES! More from techderaudios →
- Techder Audios: Zealot ZE41 VS JBL Boombox 4 "BOOSTED BASS VS BOOSTED TREBLE!?"
- Techder Audios: YEAHBOX Sonic Boom Ultra VS JBL Boombox 4 "IT BEATS THE KING!?😈😱"
- Jagist reviews: Jbl Boombox 4 Vs Zealot Ze21!!! More from Jagistreviews →
- Jagist reviews: Jbl Boombox 4 Vs Zealot S89!!!
- Jagist reviews: Jbl Boombox 4 Vs Zealot S95!!!
- Jagist reviews: Hopestar A90 Vs Jbl Boombox 4!!! Battle Of The Gods!!!
- Jagist reviews: Jbl Boombox 4 Vs Hopestar A65!!!
- Jagist reviews: Jbl Boombox 4 Firmware Updated Vs Hopestar A90!!! Rematch Of Beasts!!!
- Jagist reviews: Zealot PT21 Vs Jbl Boombox 4!!! 😁😁😁
- Jagist reviews: Jbl Boombox 4 Vs Zealot Ze41!!! Sheer Power Vs Great Clarity!!! 😍😍😍
- Jagist reviews: Jbl Boombox 4 Vs Xdobo Wow Max!!!
- GYMCADDY: Soundboks Mix Vs JBL Boombox 4 More from GYMCADDY →
- J_Strat Battles: ZEALOT ZE51 VS JBL BOOMBOX 4 (OLD FIRMWARE VERSION) 🧨🧨🧨
- Head-to-Head Comparisons
- JBL Boombox 4 vs Zealot S89
- JBL Boombox 4 vs Xdobo Wow Max
- JBL Boombox 4 vs Zealot ZE21
- JBL Boombox 4 vs Hopestar A90
- JBL Boombox 4 vs Zealot ZE41
- JBL Boombox 4 vs Harman Kardon Go + Play 2
- JBL Boombox 4 vs Harman Kardon Onyx Studio 5
- JBL Boombox 4 vs Harman Kardon Onyx Studio 9
- See all 124 comparisons