Hello everybody;

I have heard that these calibration systems found on the new yamaha (YPAO)and pioneer elite (MCACC)receivers are really useful. As I am about to purchase a new receiver I had two questions ...
1) Are they really a must have; or can I get by without them? (I'm still tempted by the NAD t763 and NAD t773).
2) Is there a product that you can buy that will do the same thing for an amp that doesn't have this technology built in?

also ... which is better... pioneer or yamaha? (I'm not trying to start a brand loyalty war...)

Thanks so much guys...