Based on the positive reviews on Amazon and a promising review in a hifi magazine, I came across the GSB 500 from Grundig. Commercially it was unfortunately not in stock, so I ordered the speaker blindly.
Advance for the better:
The sound volume is independent of the chosen music style for a device of this size really neat. The Grundig is not too focused on the bass response, which I think is good, as well as mid and high frequencies are issued fairly clean. Those who place value on real basses, is probably generally not as well served by these small speakers, even if there are candidates who can score more in this discipline (eg the Bose SoundLink).
Absolutely positive is also the processing. The device is also set up stable rather massive and by gum and fold-out stand. Downside, the size and the weight of the speaker is actually of no use as a travel speaker, but something for home use.
The GSB 500 to send now to the two aspects that have led me to back again:
Mainly I use Bluetooth connections to over radio stations to stream. The Grundig not only in making the Bluetooth connection but also with each channel change a very loud buzzing noise by itself. Would not it only when turning, ok do that other BT speakers as well, but the intrusive sounds each time you change channels I found disturbing, especially when switching sometimes more frequently.
Second reason for exclusion was the volume control. Both on an iPad 2 and Google Nexus volume control did not work consistently. Sometimes the box when adjusting the speaker volume has jumped abruptly to the highest volume, which I repeatedly chased a fright in the limbs, as it quite makes in terms of maximum volume of up listening.
Well I ended up at the BT Bamster of devil, who is my usage patterns better suited for some extra cash. No sound when changing channels, volume control via tablet and mobile phone works properly and the sound is also balanced gratifying.