The first Cambridge Audio Go was one of the first really strong budget wireless speakers. However, it had a big problem: turn the volume up too loud and it could start making parp noises because the drivers were just moving too violently.
Cambridge has fixed all that in this second version, as well as classing-up the design a bit and adding NFC and aptX. The sound has been calmed down a bit too, so this might not be for you if you want a bass monster. But, as with just about everything from Cambridge, it still sounds very good indeed.
The bonus of going for a slightly larger (but still very portable) speaker like this is that it packs-in separate main drivers and tweeters, as well as a classic bass-reinforcing radiator.