Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Marshall - Stockwell III | Anker - Boom 2 Plus |
|---|---|---|
| Output power | 30 W | 140 W |
| Battery | 27 h | 20 h |
| Low-end response | 50 Hz | 45 Hz |
| Water resistance | IPX4 | IP67 |
Between the Stockwell III and Boom 2 Plus, the Stockwell III comes out ahead in battery, while the Boom 2 Plus wins on output power / low-end response. Overall, the Stockwell III scores 68.6 and the Boom 2 Plus scores 81.8 on our Mars Score.
Which should you buy?
The Boom 2 Plus is the clear pick on raw spec strength, leading by 13.2 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the Stockwell III if you care most about battery. The biggest gaps in its favor are battery. The single most decisive one: Battery — 35.00% more. 27 h vs 20 h.
Pick the Boom 2 Plus if you care most about output power / low-end response. Its strongest claims are output power, low-end response, water resistance. The single most decisive one: Output power — 366.67% more. 140 W vs 30 W.
Both ship with comparable stereo pairing, so those specs do not separate the two — focus on the differences below.
Bottom line: the Boom 2 Plus is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Which should you buy: Marshall - Stockwell III or Anker - Boom 2 Plus?
Anker - Boom 2 Plus leads the current Mars Score by 13.2 points.The more useful decision is the trade-off behind that result: compare output power, battery, water resistance against the way you will actually use the product.
Choose Marshall - Stockwell III if…
Marshall - Stockwell III has the measurable edge on battery h.
Choose Anker - Boom 2 Plus if…
Anker - Boom 2 Plus has the measurable edge on output w, frequency low hz, ip rating.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why Marshall - Stockwell III wins
- ▲Battery — 35.00% more. 27 h vs 20 h.
Why Anker - Boom 2 Plus wins
- ▲Output power — 366.67% more. 140 W vs 30 W.
- ▲Low-end response — 5.00 Hz less. 45 vs 50.
- ▲Water resistance: IP67 (vs IPX4).
Spec comparison
Audio
| Spec | Marshall - Stockwell III | Anker - Boom 2 Plus |
|---|---|---|
| Output power | 30 W | 140 Wlead |
| Low-end response | 50 Hz | 45 Hzlead |
| Stereo pairingⓘ | true | true |
Durability
| Spec | Marshall - Stockwell III | Anker - Boom 2 Plus |
|---|---|---|
| Water resistanceⓘ | IPX4 | IP67lead |
| Weight | 1390 glead | 2700 g |
Battery
| Spec | Marshall - Stockwell III | Anker - Boom 2 Plus |
|---|---|---|
| Battery | 27 hlead | 20 h |
| USB out (powerbank) | false | truelead |