Thanks JS,If you haven't seen BigClive on YouTube, check him out. He loves to "take to bits" stuff like this. Based on the USB power banks he's looked at before, there's a good chance that the rating on this thing is wildly optimistic. The area of the solar cells does look like there's hope of a decent solar charge.
Doh!!!! Your not allowing for the fact they are CHINESE Amps, not wimpy European ones! The bet the chinglish manual says WhatsThanks JS,
yes I like BigClive's YouTube videos.
There is another advert on eBay offering a stereo amplifier with 120W output power into eight Ohms and on the power connector on the back of the amplifier case it quite clearly said 12V @ 1A.