A friend has put me onto Tripath (chip) based music amplifiers saying they are cheap to run & sound better than many very expensive models. And he's right
Well impressed I was. So impressed I ordered one from eBay - a Muse DT- 50A model.
There are a variety of companies using the Tripath chips but they are hard to buy from specialist audio shops because the sellers cannot make much of a margin on them thus denying you & me the chance to own one
You can see these amazing amps being demo'd on YouTube etc and, if you are in the market, I'd urge you to consider them. Sorry for sounding like an advert but these are interesting little amplifiers
Here's one company in the UK making & selling them. Bit pricey so maybe try eBay?
http://www.templeaudio.net/index.html