Here is the Wall of Sound (WOS) by Brothers, that claimed to be the “world’s most powerful iPod speaker. With 28 elements, the WOS offers 40Hz-20kHz frequency response, 8ohms of impedace and a max of 125-watt output power.
The Wall of Sound includes a dock for iPod players. Other than the title of most powerful iPod speaker, the WOS can probably also get the title of most expensive iPod speaker thanks to its price tag of $4495.