Different classes, so treat this as a step-up-or-not question rather than a head-to-head. The Zealot PT21 ranks #12 of 46 party speakers by sound quality at $225.86; the JBL Boombox 4 ranks #20 of 91 boombox speakers by sound quality at $549.95.
The Zealot PT21 is the longer-running choice. Dual 166mm woofers and 200W output in a lighter, more compact body than the Zealot ZE41, with a bundled wireless microphone and echo effect built in for karaoke. It is rated for 60 hours of battery against 28 for the JBL Boombox 4. It keeps a wired aux input, which the JBL Boombox 4 lacks. It has a microphone input for karaoke or announcements, which the JBL Boombox 4 lacks. The tradeoff: Unlike some other Zealot models, app-based EQ customization doesn’t appear to be fully supported yet, and IPX5 means it can handle splashes but not submersion.
The JBL Boombox 4 is the lighter, tougher option. Pretty insane output capability for the size. At 13.2 lbs (5.98 kg) it weighs noticeably less than the Zealot PT21 at 20.7 lbs (9.4 kg). It is rated IP68 against IPX5 for the Zealot PT21. Watch for: Pretty overpriced for the category.
Buy the Zealot PT21 ($225.86) for a party speaker; the JBL Boombox 4 ($549.95) suits a boombox speaker instead.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
Specifications Side By Side
| Zealot PT21 | JBL Boombox 4 | |
|---|---|---|
| Price | $225.86 | $549.95 |
| Ranked | #12 of 46 in Party Size Portable Bluetooth Speakers | #20 of 91 in Boombox Size Portable Bluetooth Speakers |
| App | No | Yes |
| Aux Input | Yes | No |
| Battery Capacity | 48000mAh (12x4000mAh) | - |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 5.4 |
| Dimensions | 21.1” x 8.6” x 11.9” (535 x 219 x 303 mm) | 20.1” x 10.2” x 8.3” (510 x 260 x 210 mm) |
| Drivers | 2x 166mm woofers + tweeters + midrange drivers | 2x 123mm woofers + 2x 20mm tweeters with passive radiators |
| EQ | Yes (Bass, Voice, Standard modes) | Yes (7 band) |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) | - |
| IP Rating | IPX5 | IP68 |
| Microphone Input | Yes (Karaoke mode with echo effect) | No |
| MicroSD Playback | Yes | No |
| Amplifier Power | 200W | 210W AC / 200W battery |
| Party Mode | Yes (PartyAdd up to 100 speakers) | Yes (Auracast) |
| Power Bank | Yes (USB-A) | 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 | 20.7 lbs (9.4 kg) | 13.2 lbs (5.98 kg) |
| Digital Aux Input | No | Yes (USB-C) |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) | SBC, LC3, AAC |
| Lights | Yes | - |
| Battery Life | 60 hours (Manufacturer specified) | 28 hours (Manufacturer specified) |
| Bass Extension (-10dB) | - | 41Hz |
| Bluetooth Latency | - | AAC 144ms, SBC 48ms |
| Maximum SPL | - | 115dB (measured by Alan Ross Reviews) |
| Removable Battery | - | Yes |
| Built-in Microphone | - | No |
| FM Tuner | - | No |
| Strap | - | No |
Watch Them Compared
Videos and reviews that test both speakers side by side.
Related Speaker Comparisons
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- Harman Kardon Go + Play 3 vs JBL Boombox 4
- JBL Boombox 4 vs JBL Partybox Encore 2
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Prices on this page were last checked October 10, 2026 at 5:37 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 PT21: $225.86 AliExpress eBay
Pros: Dual 166mm woofers and 200W output in a lighter, more compact body than the Zealot ZE41, with a bundled wireless microphone and echo effect built in for karaoke. Quite deep bass for the price, even deeper than the JBL Boombox 4 in direct comparisons.
Cons: Unlike some other Zealot models, app-based EQ customization doesn’t appear to be fully supported yet, and IPX5 means it can handle splashes but not submersion.
Full Zealot PT21 review and specifications →
| Released | Nov 2025 (11 months ago) |
|---|---|
| Amplifier Power | 200W |
| App | No |
| Aux Input | Yes |
| Battery Capacity | 48000mAh (12x4000mAh) |
| Battery Life | 60 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 21.1” x 8.6” x 11.9” (535 x 219 x 303 mm) |
| Drivers | 2x 166mm woofers + tweeters + midrange drivers |
| EQ | Yes (Bass, Voice, Standard modes) |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) |
| IP Rating | IPX5 |
| Lights | Yes |
| MicroSD Playback | Yes |
| Microphone Input | Yes (Karaoke mode with echo effect) |
| Omnidirectional | No |
| Party Mode | Yes (PartyAdd up to 100 speakers) |
| Power Bank | Yes (USB-A) |
| Power Input | Type-C |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 20.7 lbs (9.4 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Jagist reviews: Zealot PT21 Vs Jbl Boombox 4!!! 😁😁😁 More from Jagistreviews →
- Techder Audios: Zealot PT21 - Soundtest "BUDGET PARTYBOX WITH BASS ?" More from techderaudios →
- Jagist reviews: Zealot PT21 Vs Zealot Ze21!!! 🥰😍🥰
- Jagist reviews: Zealot PT21 Unboxing And Review!!! 😈😈😈
- Techder Audios: Zealot PT21 VS Yeahbox Sonic Boom Ultra "BASS VS QUALITY BASS!?"
- Jagist reviews: Zealot Ze41 Vs Zealot PT21!!! BATTLE OF THE BROTHERS!!! 😝😝😝
- Jagist reviews: Zealot PT21 Vs Yeahbox Sonic Boom Max3!!! 💥💥💥
- Jagist reviews: Zealot PT21 Vs Zealot S89!!! 😈😈😈
- Jagist reviews: Zealot PT21 Vs LG xboom Stage301!!! 🫣🫣🫣
- Jagist reviews: Zealot PT21 Slim Back Rattle Fix!!!😇😇😇
- Head-to-Head Comparisons
JBL Boombox 4: $549.95 Amazon B&H Photo Video 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 vs Boombox 3 - old one sounding better? 🤔 More from Oluv’Sone →
- 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
- JOY‘s 🎧3D🔈Audio-Show: JBL Boombox 4 - finally a real BOOMbox from JBL 👏
- Alan Ross Reviews: JBL Boombox 4 HUMILIATES Brane X?! Ultimate Bass Battle! More from alanrossreviews →
- Alan Ross Reviews: JBL Boombox 4 Compared to Boombox 3 & 3 WiFi – Worth the Upgrade?
- Alan Ross Reviews: JBL Boombox 4 distortion fest bonanza! how bad can it be lol 🤣
- Jagist reviews: Jbl Boombox 4 Vs Zealot Ze21!!! More from Jagistreviews →
- Techder Audios: JBL Boombox 4 VS Zealot ZE21 BATTLE OF THE BOOMBOXES! More from techderaudios →
- Dominik Reviews: Zealot S89 vs JBL Boombox 4 - JBL Alternative? Sound Test More from Dominik Reviews →
- Jagist reviews: Jbl Boombox 4 Vs Zealot S89!!!
- Jagist reviews: Jbl Boombox 4 Vs Zealot S95!!!
- M1MTechChannel: Welche JBL Partybox ist die BESTE ? Alle Partyboxen im Vergleich | 2026 More from M1MTechChannel →
- M1MTechChannel: JBL BOOMBOX 4 - Einfach komplett GEISTESKRANK
- Jagist reviews: Hopestar A90 Vs Jbl Boombox 4!!! Battle Of The Gods!!!
- Jagist reviews: Jbl Boombox 4 Vs Hopestar A65!!!
- Alan Ross Reviews: JBL Distortion Fest vs my favorite speaker today! I wasn’t expecting this!
- Jagist reviews: Jbl Boombox 4 Firmware Updated Vs Hopestar A90!!! Rematch Of Beasts!!!
- GYMCADDY: Soundboks Mix Vs JBL Boombox 4 More from GYMCADDY →
- Jagist reviews: Zealot PT21 Vs Jbl Boombox 4!!! 😁😁😁
- Jagist reviews: Jbl Boombox 4 Vs Zealot Ze41!!! Sheer Power Vs Great Clarity!!! 😍😍😍
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