I Need High-End home theatre receiver – which brand should I go for – Onkyo, Denon, Yamaha, Pioneer..?
This really depends on your price range and your definition of “high end”. Onkyo and Denon are a clear cut above any of the others you mentioned. A couple of comparable brands that haven’t been mentioned are Marantz and Integra (which is to Onkyo what Sony ES is to Sony). For a truly high end receiver, consider NAD (their modular component design is awesome http://is.gd/3ovl) and Rotel (http://www.rotel.com/NA/products) which are both a step above Onkyo, Denon, etc. – but more expensive. Note that in some cases, these manufacturers may lag behind a bit in features (HDMI 1.3, Dolby TrueHD, etc.) but they are still better sounding due to the superior engineering in the preamp and power amp circuitry. Finally, if you’re truly looking for high end performance (and price is no object), you should seriously consider separates – a preamp/processor (i.e. Lexicon –