Marshall has officially unveiled the Stockwell III, the latest version of its portable Bluetooth speaker, bringing significant upgrades to battery life, repairability, and durability.

The new Stockwell III retains Marshall’s signature amplifier-inspired design while introducing several practical improvements aimed at extending the speaker’s lifespan. Most notably, the speaker now delivers more than 40 hours of wireless playback on a single charge—double the battery life offered by the previous-generation model.

A major highlight is the inclusion of a replaceable battery, allowing users to swap it out when capacity begins to degrade over time. Marshall has also designed several other components to be user-replaceable, including the carrying strap, front and rear grilles, and the protective silicone outer sleeve. This move improves long-term sustainability and could help owners keep the speaker looking and performing like new for years.

The upgraded battery serves a dual purpose, functioning as a power bank that can charge smartphones and other devices via USB-C. Marshall has also improved the speaker’s ruggedness with an IP55 rating, providing better protection against dust and water splashes compared to its predecessor.

On the control side, the brass-finished top panel has been redesigned with additional functionality. A new customizable M-button lets users switch between preset sound profiles, while a dedicated media control button makes it easier to play, pause, and skip tracks directly from the speaker.

The Stockwell III continues to feature Marshall’s portable form factor with 360-degree sound output, making it suitable for both indoor listening and outdoor use. The speaker is scheduled to go on sale beginning August 4 and will be available through Marshall’s online store and select retailers.