The Ultimate Ears Boom, made by the prestigious audio company bought out by Logitech a couple of years ago, is a consumer-nice portable speaker that’s made to go with you wherever you desire to take your tunes. Built from a combination of shock-absorbent plastic and water-resistant armour, the cylindrical Boom is made to take some punishment. It’s able to withstand a drop from several feet onto difficult concrete, hold playing in a downpour and even shrug off mud or spilt drinks thanks to a stain-resistant treatment, all of which means it could be the ideal portable speaker for taking to a festival. The built-in karabiner cut lets you hook the speaker to your rucksack, or it will just as easily fit in a car cup holder or bicycle bottle holder. Inside, there are two 2in drivers and two passive radiators that point outwards at different directions to surround you with sound. The speaker works well outside and when there are no walls for audio to bounce off, especially compared to more traditional directional speakers. The Boom produces impressively loud audio, which has a reasonably sure mid-range but a slight lack of bass. We’ve seen similarly-sized speakers with more rumble than this. The mesh material covering the speaker drivers is acoustically transparent, so it doesn’t muffle the sound, but we would have liked a crisper high end; some of the detail gets lost during hectic electronic and rock songs. The speaker uses the SBC Bluetooth codec, which is lossier than the higher-quality aptX codec, although the difference is rarely perceptible in small portable speakers. There’s no analogue input for non-Bluetooth sources.