The smallest reasonably good speaker at the best possible price would be the Wharfedale Diamond 9.0 for about £40/pr, though the original retail on them was considerably higher than that.
WHARFEDALE DIAMOND 9.0Black Speakers Per Pair
Thanks - they're a similar size to the JBL Control 1, so not bad.
You have to weigh size vs performance. Sure you can get tiny 1 inch speakers, just don't expect them to be very loud, or very good, or to have much impact.
You can only go just so small before the speakers stop doing what you want done.
Which brings up another point, what is it you want done?
Indeed.
Well she loves her music, but she's only 10 and there's only so much quality she needs. I don't think it matters if she's short of bass. What I think would be good (and of course I could be wrong) is to be able to give her stereo sound, so the music sounds a bit like music. Her room is cluttered with the sort of rubbish children have, but the wall opposite her bed is clear, and it makes sense to put speakers there. But small would be good, she's not a bachelor.
I think we can safely say 1" speakers just aren't going to cut it. But I don't think we need to go big, as reading people rave about their Sonos makes me more than sure the Play 1s would be good enough. The problem with the Play 1 is the price. I was also put off by having to run power cables around the walls, but I think that could be solved.
You mention SONOS which are active Network Speakers, but you implied that you wanted straight forward passive speakers and an amp.
So, what will be the source of the sound for this amp and speakers?
Give us a working budget?
I was thinking of a Chromecast Audio, that she can run from her tablet / phone (that's the phone she gets in a year's time). I have a spare Amp, and thought I could try and get a passive, non networked version of the Play1, and run thinish speaker cables.
Budget - well if I can get some speakers that sound ok for between £40 and £70 (just using the examples above), then that would be sweet.
If you have any special requirement, you need to explain them to us
The Devil is always in the Details.
Steve/bluewizard
Cheap passive speakers a similar size to Play1s, that I can mount on the wall. Bonus points for white/silver/purple
Many thanks everyone for all the help, much appreciated