The Wonderboom 3 from Ultimate Ears sounds pleasant and surprisingly spacious. The optional outdoor mode tickles out a higher maximum volume at the touch of a button, but this is at the expense of the sound quality. The battery life of over 18 hours is enough for long days, and the huge volume buttons can be operated accurately even at nighttime beach parties.

A powerful bass, clearly audible details and a balanced, lively sound - that's what the perfect Bluetooth speaker should sound like. However, good sound quality is not everything: Stiftung Warentest expects a test winner to be easy to use, to have a long-lasting battery and to offer practical additional functions.