I really like Marshall. During all my years spent in the rehearsal room, behind the drums, it was the combination of a Fender Stratocaster and a Marshall AFD100 that sounded best, and Zound Industries' affordable, stylish, well-built Bluetooth speakers have been good, pretty much across the board. I have given high marks to Stanmore, Willen, Emberton, and Woburn, and I always look forward to testing more new products from Marshall.
In the wireless, battery-powered Bluetooth speaker segment, Marshall has been at the top alongside JBL in terms of how accurately ingenious and well-balanced their DSP has been, which has allowed them to produce big sound from small drivers/speakers in a way that at times resembles pure magic (and I am referring primarily to Emberton).
Kilburn is one of Marshall's larger Bluetooth speakers, but still significantly smaller and more portable than, for example, Woburn and Stanmore. It's 27 centimetres long and 15 centimetres wide, weighs 3.9 kilograms, and has a built-in battery that plays your music for nearly 50 hours per charge, which is obviously very good. There is fast charging, which in the case of the Kilburn III gives eight hours of playback time via 20 minutes of charging using USB-C. The design is as iconic as ever, which means that this speaker looks like a small leather-covered miniature of Marshall's fantastically stylish old guitar amplifiers. On the top, where all the controls are located, there is a brass plate and the controls are of very good quality. Zound Industries has also added a switch button that allows you to skip to the next song (or the previous one) in your playlist without touching your mobile phone.
Marshall describes the sound of the Kilburn III as {360° True Stereophonic Sound}, which is achieved via their signature chip/DSP and three Class C amplifiers that power three drivers. In the middle is a 4" bass driver, and on either side of it are two 2" drivers that handle the midrange and treble (1 x 30 watts and 2 x 10 watts). The Kilburn III has an AUX input (which is all too often missing in many of its competitors' models) and can double as a power bank for those who want to use the battery's 50 hours to charge their mobile phone, iPad, or laptop.
Lots of battery life, lots of immersive sound, but the profile is messier than usual.
The Kilburn III is well equipped, stylishly designed, and has features that feel sensible and well balanced in relation to the type of speaker it is. It's this reason that it's a shame that I don't really like the way it sounds. Marshall's signature sound is warm, bassy, playful, and has a chronic tendency to do rock music, with distorted guitars, greater justice than Bluetooth speakers from virtually all competitors. Marshall is pretty much always tuned for rock, which it should be, and it always works in my experience. The Kilburn III certainly has deep and tight bass reproduction, but there is resonance in the speaker that I rarely hear in other speakers from Zound Industries, and the midrange is thin and a bit messy. There is plenty of control over the voice reproduction, but I find the overall sound to be scattered and a bit restless, which is surprising in the case of Marshall.
£300 for this is ultimately at least £75 too much.
When I compare the Kilburn III to the several years old and significantly cheaper JBL Extreme III (which is about the same physical size), it's clear that the sound is a little too unbalanced and lacks the control that the JBL speaker still offers. Sure, the Extreme III offers 20 hours of battery life while the Kilburn III lasts a full 50 hours, but otherwise I would say that I prefer the JBL speaker in all respects, especially considering that it costs £180 while the Kilburn III goes for a hefty £300.