JBL Partybox Encore Essential vs Yeahbox Sonic Boom Ultra

Last updated: September 16, 2026

Short answer: the JBL Partybox Encore Essential. It ranks #7 of 75 boombox speakers by sound quality at $299.95; the Yeahbox Sonic Boom Ultra ranks #10 and costs $349.20, which makes this an easy call rather than a real tradeoff.

JBL Partybox Encore Essential vs Yeahbox Sonic Boom Ultra

What the JBL Partybox Encore Essential offers: JBL Partybox Encore Essential uses 135mm woofer + 2x 44mm tweeters. Its 5.9 kg, claimed 6 hours (Manufacturer specified) battery life, IPX4 protection, aux input, up to 110dB and stereo playback make it a practical option for its intended room or portable use. Watch for: Bass is limited by its 38Hz specification.

What the Yeahbox Sonic Boom Ultra offers: By far the loudest boombox tested against it, hitting 106-107dB, roughly 3-5dB louder than the JBL Boombox 4, Zealot ZE41, Tribit Stormbox Blast 2, W-King X20, and Hopestar A90/A95. The massive 6x9in racetrack woofer reaches audible bass down to around 30Hz on the Country EQ preset, and a teardown confirmed genuinely robust internals: a thick vented voice coil and a dedicated crossover output per driver. HDMI ARC input/output lets it double as a TV soundbar, a feature none of its direct competitors offer. Watch for: The 500W peak-power rating doesn’t fully hold up: it gets noisy above roughly 80-90% volume, and the midrange isn’t fully refined, sometimes sitting a touch too forward. The custom EQ in the app noticeably reduces bass output compared to the factory presets and doesn’t persist after the speaker powers off. No Auracast, no removable battery, a plastic handle with some flex, and heavy at 11kg (24lb) for $388. Most of the sound-quality coverage comes from enthusiast listening-test comparisons rather than independent measurement.

Buy the JBL Partybox Encore Essential. It ranks higher for sound quality than the Yeahbox Sonic Boom Ultra and costs less, which settles it without a real tradeoff to make.

Still deciding? The full Portable Bluetooth rankings cover every ranked option.

Specifications Side By Side

JBL Partybox Encore Essential Yeahbox Sonic Boom Ultra
Price$299.95$349.20
Ranked#7 of 75 in Boombox Size Portable Bluetooth Speakers#10 of 75 in Boombox Size Portable Bluetooth Speakers
AppYes (JBL PartyBox app)Yes
Aux InputYesYes
Aux Latency17ms-
Bass Extension (-10dB)38Hz-
Battery Life6 hours (Manufacturer specified)-
Bluetooth CodecsSBCSBC (inferred; additional codecs unverified)
Built-in MicrophoneNo-
EQYes (3 band App EQ)Yes (Country, Classic, and custom app EQ; custom settings don't persist after the app closes)
IP RatingIPX4IPX6
Bluetooth Latency100ms-
Party ModeYes (PartyBoost up to 100 speakers)No (TWS stereo pairing of 2 units only, no Auracast)
Power BankYes (USB-A, 5V/0.5A)-
Power InputAC Power cordUSB-C (60W fast charging)
StereoYesYes
OmnidirectionalNoNo
TWSYesYes
USB PlaybackYesYes
Weight13 lbs (5.9 kg)24.3 lbs (11 kg)
Bluetooth Version5.16.0
Amplifier Power100W RMS320W RMS / 500W Peak
Dimensions10.9" x 12.9" x 11.5" (276 x 327 x 293 mm)23.4" x 9.8" x 12.3" (595 x 248 x 313 mm)
Drivers135mm woofer + 2x 44mm tweeters6x9in racetrack woofer (200W) + 2x 4.5in midrange (40W each) + 2x tweeters (20W each), true 3-way
Maximum SPL110dB (measured by Alan Ross Reviews)-
Digital Aux InputNoNo
Battery Capacity-45000mAh (Reviewer estimated)
Inputs-HDMI ARC (in/out, usable as a TV soundbar), AUX in/out, USB drive, microSD, optional wired mic
MicroSD Playback-Yes
Lights-Yes

More top alternatives to JBL Partybox Encore Essential:

Prices on this page were last checked September 16, 2026 at 12:41 AM 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

JBL Partybox Encore Essential: $299.95 Amazon eBay

JBL Partybox Encore Essential ranking card

Pros: JBL Partybox Encore Essential uses 135mm woofer + 2x 44mm tweeters. Its 5.9 kg, claimed 6 hours (Manufacturer specified) battery life, IPX4 protection, aux input, up to 110dB and stereo playback make it a practical option for its intended room or portable use. Measured bass extension of 38Hz (-10dB).

Cons: Bass is limited by its 38Hz specification.

Amplifier Power100W RMS
AppYes (JBL PartyBox app)
Aux InputYes
Aux Latency17ms
Bass Extension (-10dB)38Hz
Battery Life6 hours (Manufacturer specified)
Bluetooth CodecsSBC
Bluetooth Latency100ms
Bluetooth Version5.1
Built-in MicrophoneNo
Digital Aux InputNo
Dimensions10.9" x 12.9" x 11.5" (276 x 327 x 293 mm)
Drivers135mm woofer + 2x 44mm tweeters
EQYes (3 band App EQ)
IP RatingIPX4
Maximum SPL110dB (measured by Alan Ross Reviews)
OmnidirectionalNo
Party ModeYes (PartyBoost up to 100 speakers)
Power BankYes (USB-A, 5V/0.5A)
Power InputAC Power cord
StereoYes
TWSYes
USB PlaybackYes
Weight13 lbs (5.9 kg)

Yeahbox Sonic Boom Ultra: $349.20 Amazon eBay

Yeahbox Sonic Boom Ultra ranking card

Pros: By far the loudest boombox tested against it, hitting 106-107dB, roughly 3-5dB louder than the JBL Boombox 4, Zealot ZE41, Tribit Stormbox Blast 2, W-King X20, and Hopestar A90/A95. The massive 6x9in racetrack woofer reaches audible bass down to around 30Hz on the Country EQ preset, and a teardown confirmed genuinely robust internals: a thick vented voice coil and a dedicated crossover output per driver. HDMI ARC input/output lets it double as a TV soundbar, a feature none of its direct competitors offer.

Cons: The 500W peak-power rating doesn’t fully hold up: it gets noisy above roughly 80-90% volume, and the midrange isn’t fully refined, sometimes sitting a touch too forward. The custom EQ in the app noticeably reduces bass output compared to the factory presets and doesn’t persist after the speaker powers off. No Auracast, no removable battery, a plastic handle with some flex, and heavy at 11kg (24lb) for $388. Most of the sound-quality coverage comes from enthusiast listening-test comparisons rather than independent measurement.

Amplifier Power320W RMS / 500W Peak
AppYes
Aux InputYes
Battery Capacity45000mAh (Reviewer estimated)
Bluetooth CodecsSBC (inferred; additional codecs unverified)
Bluetooth Version6.0
Digital Aux InputNo
Dimensions23.4" x 9.8" x 12.3" (595 x 248 x 313 mm)
Drivers6x9in racetrack woofer (200W) + 2x 4.5in midrange (40W each) + 2x tweeters (20W each), true 3-way
EQYes (Country, Classic, and custom app EQ; custom settings don't persist after the app closes)
IP RatingIPX6
InputsHDMI ARC (in/out, usable as a TV soundbar), AUX in/out, USB drive, microSD, optional wired mic
LightsYes
MicroSD PlaybackYes
OmnidirectionalNo
Party ModeNo (TWS stereo pairing of 2 units only, no Auracast)
Power InputUSB-C (60W fast charging)
StereoYes
TWSYes
USB PlaybackYes
Weight24.3 lbs (11 kg)