Short answer: the Harman Kardon Go + Play 3. It ranks #3 of 98 boombox speakers by sound quality, rated 4.4/5, at $385. The Zealot S78 ranks #97, rated 2.0/5, at $159.68, $225.32 cheaper, a saving that is not big enough to make up the sound-quality gap.
The Harman Kardon Go + Play 3 is the better-sounding option. Warm sound with boosted bass. It supports AAC Bluetooth, which the Zealot S78 lacks. The tradeoff: Just a little over half as loud as the higher rated boomboxes.
The Zealot S78 is the longer-running, tougher pick. A robust 9.7 lbs (4.4 kg) party speaker with claimed 120W RMS output, IP67 protection, USB-C charging, a power-bank function, aux, USB and microSD playback, TWS pairing and multiple EQ modes. It is rated for 40 hours of battery against 8 for the Harman Kardon Go + Play 3. It is rated IP67, while the Harman Kardon Go + Play 3 has no water resistance. Watch for: At high volume, reviews report distortion and fluctuating level, so its headline power is more useful below its maximum setting.
Buy the Harman Kardon Go + Play 3. It is rated higher for sound quality, and saving $225.32 with the Zealot S78 does not make up for the sound-quality gap.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
Specifications Side By Side
| Harman Kardon Go + Play 3 | Zealot S78 | |
|---|---|---|
| Price | $385 | $159.68 |
| Ranked | #3 of 98 in Boombox Size Portable Bluetooth Speakers | #97 of 98 in Boombox Size Portable Bluetooth Speakers |
| App | Yes (Harman Kardon One app) | No |
| Aux Latency | 112ms | - |
| Bass Extension (-10dB) | 35Hz | - |
| Battery Life | 8 hours (Manufacturer specified) | 40 hours (Manufacturer specified) |
| Built-in Microphone | Yes | No |
| EQ | Yes (App EQ) | Yes (multiple modes) |
| IP Rating | None | IP67 |
| Bluetooth Latency | 120ms | - |
| Maximum SPL | 103dB (measured by Alan Ross Reviews) | - |
| Power Input | AC Power brick | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 10.4 lbs (4.7 kg) | 9.7 lbs (4.4 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, AAC | SBC |
| Power Bank | Yes | Yes (USB-A) |
| Party Mode | No | No |
| USB Playback | No | Yes |
| Bluetooth Version | 5.2 | 5.3 |
| Amplifier Power | 160W RMS | 120W RMS / 150W peak |
| Dimensions | 17.3” x 9.4” x 7.6” (439 x 240 x 192 mm) | 16.1” x 6.6” x 7.3” (410 x 167 x 185 mm) |
| Aux Input | Yes | Yes |
| Drivers | 1x 130mm (5”) subwoofer + 2x 70mm midrange drivers + 2x 20mm tweeters | 2x ~120mm (4.72”) woofers + 2x ~42mm tweeters + 2x passive radiators |
| Digital Aux Input | No | No |
| Strap | No | Yes (detachable shoulder strap) |
| MicroSD Playback | - | Yes |
Related Speaker Comparisons
More worthwhile head-to-heads for Harman Kardon Go + Play 3:
- 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.
As an eBay Partner, we may be compensated if you make a purchase.
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
- See all 63 comparisons
Zealot S78: $159.68 Amazon $159.68 AliExpress $91.38 eBay
Pros: A robust 4.4kg party speaker with claimed 120W RMS output, IP67 protection, USB-C charging, a power-bank function, aux, USB and microSD playback, TWS pairing and multiple EQ modes. Reviews find it very loud with useful bass and long claimed battery life, making it a credible choice for outdoor gatherings.
Cons: At high volume, reviews report distortion and fluctuating level, so its headline power is more useful below its maximum setting. It has no app-based EQ, and the bass and midrange refinement do not match better-established boombox speakers; assess its sound in person if tonal accuracy matters.
Full Zealot S78 review and specifications →
| Released | May 2023 (3 years ago) |
|---|---|
| Amplifier Power | 120W RMS / 150W peak |
| App | No |
| Aux Input | Yes |
| Battery Life | 40 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 16.1” x 6.6” x 7.3” (410 x 167 x 185 mm) |
| Drivers | 2x ~120mm (4.72”) woofers + 2x ~42mm tweeters + 2x passive radiators |
| EQ | Yes (multiple modes) |
| IP Rating | IP67 |
| MicroSD Playback | Yes |
| Omnidirectional | No |
| Party Mode | No |
| Power Bank | Yes (USB-A) |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | Yes (detachable shoulder strap) |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 9.7 lbs (4.4 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Jay’s Straight Up Reviews & More: DBSOARS F29 Max vs Zealot S78 🛜 (5B) Budget Bluetooth Boombox Basement Battle 🔊 Bass Modes Enabled More from JaysStraightUpReviews →
- Jay’s Straight Up Reviews & More: W-King X20 vs Zealot S78 Bluetooth Boombox Battle Outdoor Tailgater Special 🚗 Let the Whoopin’ Begin
- Head-to-Head Comparisons