Marshall Kilburn III Bluetooth speaker review

The Marshall Kilburn III is the third iteration of the brand’s hero Bluetooth speaker. Louder, clearer, and tougher than its predecessors, it combines the iconic amp-inspired design Marshall is known for with a number of welcome refinements, including improved battery life and a wider soundstage.

It may be portable, but this is no festival trinket. At 2.8kg, the Kilburn III isn’t something you’ll throw casually in a backpack - but if your idea of portable means taking music from the garden to the garage, this could be exactly what your tour manager ordered.

Marshall Kilburn II: Design

Instantly recognisable as a member of the Marshall family, the Kilburn III looks exactly as it should. From the textured black leatherette casing to the brassy control plate and crimson-lined carry strap, this is a speaker that exudes rock‘n’roll swagger. The knurled volume knobs are tactile and purposeful, while flipping the toggle switch for power adds a touch of theatre to what’s usually a boring button press.

On the rear you’ll find a bass port and a USB-C in/out socket for charging, plus a 3.5mm aux input, for those who don’t want to commit wholly to Bluetooth. There’s no Wi-Fi support, though. This isn’t a smart speaker, so don’t ask it to double as an egg timer.

It does however have an IP54 rating, meaning it can withstand dust and the odd splash of rain (or beer).

Marshall Kilburn II: Features

Battery life is the headline attraction here. Boasting more than 50 hours of playback on a single charge, more than double that of its predecessor, that’s enough for a weekend long party before the well runs dry.

Control is shared between those beautifully tactile knobs and the Marshall Bluetooth app which unlocks EQ presets and offers a few fine-grained tweaks; the app also lets you specify placement (near-wall or free-standing), helping optimise the tuning.

Helpfully, the Kilburn III even doubles as a charging bank. Plug your phone into the USB-C port and you can juice up while you jam out.

Highly efficient Bluetooth 5.3 goes some way to explaining the speaker’s excellent battery life, as well as ushering in Auracast compatibility

Marshall Kilburn III: Sound

This portable Bluetooth speaker sounds big and imposing, which is kind of the point.

Marshall describes the driver configuration as 360° True Stereophonic Sound, and while it doesn’t really offer full surround sound, it does deliver impressively wide imaging, especially in medium-sized rooms.

The soundstage may not be omnidirectional, but it’s more immersive than the front-firing mono setups of many rivals. It doesn’t ‘hollow out’ as you move around the speaker, doing your business.

Under the hood are three Class D amps, totalling 50W: one 30W amp driving a forward-facing 4-inch woofer, while two more 10W amps power a pair of angled tweeters, placed left and right.

Bass is tight and plentiful, thanks to a frequency response that dips as low as 45Hz. That’s not subwoofer territory, but it still slams. On tracks like Royal Blood’s Out Of The Black, the low end hits hard without wobbling the rhythm, the sound is precise and punchy.

Marshall quotes a drop to 45Hz, and it certainly feels that deep. On Yungblud’s Lowlife, the Kilburn III opens with convincing sub-bass. Airbourne’s Gutsy similarly flexes with drive and punch, handling fast kick drums with easy confidence.

Midrange, though, is where this speaker really earns its stripes. Vocals sit forward and textured. As Alice Cooper snarls Up All Night, the snare hits are tight and guitars feel authentically greasy. That’s a Marshall hallmark: the grit and swagger of stage sound, downsized for easy digestion.

Even semi-acoustic material fares well. Robert Plant’s Everybody’s Song gleams with upper-register detail, while crowd ambience on Yungblud’s Changes (Live At Villa Park) spreads wide, with vocals remaining front and emotionally present.

But Tool's prog-metal masterwork Jambi is a challenge for any Bluetooth speaker, but the Kilburn III is undaunted by its rhythmic complexity. Vocals are forward and full of life, with just enough grit to complement guitars in the mix.

This is especially noticeable on high-octane punk and hard rock - this speaker is tailor made for The Clash’s Safe European Home or The Bronx’s Heart Attack American.

While the Kilburn III can play loud, it also impressed me at low volumes, retraining its characteristic richness and separation even at modest levels.

The alternatives

JBL Flip 7
If portability is a prime reason to buy, then the JBL Flip 7 could well be a better wireless bet. Less than half the size of the Kilburn III, this feisty fashion icon sounds great (for its size) and has an IP68 waterproof and dustproof rating. Battery life is rated up to 16 hours. It comes with Bluetooth 5.4 and Auracast compatibility, and sells for a tempting £129.99.

LG Xboom Stage
Tuned by Will.I.Am, the stereo Bluetooth Xboom stage is styled after a stage monitor and features a potent 120W power output, delivered via a 6.5-inch woofer and 2.5-inch midrange. Battery life is rated at 12 hour battery life. The speaker also has Dual-bar AI lighting, able to sync with your tunes. Well worth consideration