There are speakers that are just that . . . speakers. The powered ones (either battery or AC adaptor) are just ‘amplified’. Like the ones you can buy for your computer; most are amplified because your computer puts out such a weak signal that you can’t hear them otherwise.
And remember, your Fuze only puts out about 60mw. Enough for earbuds or small headphones, but it isn’t designed to drive anything larger. Most small ‘un-powered’ speakers are going to sound pretty bad with this miniscule signal from the headphone jack.
I would get a pair that are ‘marketed’ towards computer add-on speakers. They even have some with sub-woofers! These will be powered (usually by AC) & probaby sound pretty good. The battery-powered ones sound good too, but they’re a pain because you have to remember to turn them off, or the power will drain out and the next time you want to use them, they’ll be dead, then you’ve got to hurt around for more C battteries. It can get expensive unless you use rechargeables, and then you have to remember to charge them 
