Marshall Stockwell III vs Soundcore Motion Boom

Last updated: September 16, 2026

Short answer: the Soundcore Motion Boom. It ranks #14 of 78 large speakers by sound quality at $109.99; the Marshall Stockwell III ranks #56 and costs $249.99, so there is little reason to consider the other one.

Marshall Stockwell III vs Soundcore Motion Boom

What the Marshall Stockwell III offers: 40+ hour battery life with a user-replaceable battery, strap, sleeve and grilles. Doubles as a USB-C power bank. IP55 dust/water resistance. App includes parametric EQ, a Soundstage widening control, and wall/corner placement compensation. Endless-rotation control knobs. Watch for: Highs are recessed by default and need the treble control maxed to compensate, still lacking detail even then. Bass tends to sound resonant and boomy, with reported frequency cancellation and phase issues on complex material that EQ doesn’t fully resolve. Oluv’s A/B testing against the outgoing Stockwell 2 finds the default tuning muffled and muddy enough to prefer the seven-year-old original out of the box, and output loses dynamics and bass while turning harsh well below maximum volume. No aptX support.

What the Soundcore Motion Boom offers: 30W loud bass-heavy sound, excellent budget-friendly value. 10,000mAh battery for 24 hours claimed (15-18 hours with BassUp engaged at high volume). Waterproof, buoyant design, convenient carry handle. PowerIQ USB port charges devices. BassUp feature works well with clear mids/highs. Watch for: Not as neutral or detailed as other top ranked speakers

Buy the Soundcore Motion Boom. It ranks higher for sound quality than the Marshall Stockwell III and costs less, so there is no real case for the other one.

If battery life is a priority, the Marshall Stockwell III is rated for 40 hours versus 24 hours for the Soundcore Motion Boom.

Looking for alternatives? See the complete Portable Bluetooth rankings.

Specifications Side By Side

Marshall Stockwell III Soundcore Motion Boom
Price$249.99$109.99
Ranked#56 of 78 in Large Size Portable Bluetooth Speakers#14 of 78 in Large Size Portable Bluetooth Speakers
Drivers1x 3" woofer, 2x 1.75" wide-band drivers2x 63.5mm titanium fullrange drivers + 2x passive radiators
Frequency Response54Hz - 20kHz (Manufacturer specified)-
Amplifier Power44W30W
Battery Life40+ hours (Manufacturer specified)24 hours (Manufacturer specified)
Bluetooth Version5.35.0
Bluetooth CodecsSBC, AAC, LE Audio with LC3SBC
IP RatingIP55IPX7
Weight2.9 lbs (1.3 kg)3.3 lbs (1.5 kg)
Dimensions7.1" x 6.4" x 2.9" (180 x 162 x 74 mm)13.6" x 7.9" x 5.8" (346 x 200 x 148 mm)
AppYesYes
EQYes (parametric, via app)Yes
Aux InputYesNo
Digital Aux InputNoNo
Power BankYesYes (USB-A)
Power InputUSB-CUSB-C
StereoPartiallyYes
OmnidirectionalYesNo
Bass Extension (-10dB)-53Hz
Bluetooth Latency-170ms
Maximum SPL-106dB (measured by Alan Ross Reviews)
Party Mode-No
TWS-Yes
Built-in Microphone-Yes

More worthwhile head-to-heads for Soundcore Motion Boom:

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

Marshall Stockwell III: $249.99 Marshall eBay

Marshall Stockwell III ranking card

Pros: 40+ hour battery life with a user-replaceable battery, strap, sleeve and grilles. Doubles as a USB-C power bank. IP55 dust/water resistance. App includes parametric EQ, a Soundstage widening control, and wall/corner placement compensation. Endless-rotation control knobs.

Cons: Highs are recessed by default and need the treble control maxed to compensate, still lacking detail even then. Bass tends to sound resonant and boomy, with reported frequency cancellation and phase issues on complex material that EQ doesn’t fully resolve. Oluv’s A/B testing against the outgoing Stockwell 2 finds the default tuning muffled and muddy enough to prefer the seven-year-old original out of the box, and output loses dynamics and bass while turning harsh well below maximum volume. No aptX support.

Amplifier Power44W
AppYes
Aux InputYes
Battery Life40+ hours (Manufacturer specified)
Bluetooth CodecsSBC, AAC, LE Audio with LC3
Bluetooth Version5.3
Digital Aux InputNo
Dimensions7.1" x 6.4" x 2.9" (180 x 162 x 74 mm)
Drivers1x 3" woofer, 2x 1.75" wide-band drivers
EQYes (parametric, via app)
Frequency Response54Hz - 20kHz (Manufacturer specified)
IP RatingIP55
OmnidirectionalYes
Power BankYes
Power InputUSB-C
StereoPartially
Weight2.9 lbs (1.3 kg)

Soundcore Motion Boom: $109.99 Amazon eBay

Soundcore Motion Boom ranking card

Pros: 30W loud bass-heavy sound, excellent budget-friendly value. 10,000mAh battery for 24 hours claimed (15-18 hours with BassUp engaged at high volume). Waterproof, buoyant design, convenient carry handle. PowerIQ USB port charges devices. BassUp feature works well with clear mids/highs. Measured bass extension of 53Hz (-10dB).

Cons: Not as neutral or detailed as other top ranked speakers

Amplifier Power30W
AppYes
Aux InputNo
Bass Extension (-10dB)53Hz
Battery Life24 hours (Manufacturer specified)
Bluetooth CodecsSBC
Bluetooth Latency170ms
Bluetooth Version5.0
Built-in MicrophoneYes
Digital Aux InputNo
Dimensions13.6" x 7.9" x 5.8" (346 x 200 x 148 mm)
Drivers2x 63.5mm titanium fullrange drivers + 2x passive radiators
EQYes
IP RatingIPX7
Maximum SPL106dB (measured by Alan Ross Reviews)
OmnidirectionalNo
Party ModeNo
Power BankYes (USB-A)
Power InputUSB-C
StereoYes
TWSYes
Weight3.3 lbs (1.5 kg)