Watts, and clarity.

Watts don't clarify sound quality, they just make poor quality sound louder if it's a cheap high powered amp.

Design and parts quality clarify sound. People don't pay big bucks for ARC just because of the name. If ARC delivered AMP's with SS Rotel sound, and ARC prices, they would go out of business in a jiff.

Some people can hear, some people can not; if you are one of those who thinks a powerful mid fi amp sounds as good as a less powered high end amp, then by all means exclude the expensive amp from your shopping list.

Orpheus10, 
Well stated. Power will not adequately substitute  for a lack of needed quality. If it were simply about increased power then every manufacturer would just produce 1000 watt amplifiers and the  "clarity"  issue is resolved.
Charles 

Sorry for not being clearer about the source of the "scissors" snap. I got this from a video on Youtube called "Miss Hologram". I would cut and paste it for you but I am on my Mom's computer and she has an easy set up because she is not tech savvy. I actually cannot copy and paste with it. Anyway at about 6:06 into the video Bob Carver discusses his friend that did the testing. WARNING, the video is extremely corny, it was the early 80's after all and this was when he was drumming up business for his second company, Carver Corp. 

As far as amps go, I already have some Carver m-4 t's that sound great as long as the impedance of the speakers does not dip below 4 ohms.

Watts on second. 

Thanks for the responses, although judging the context there are some who may not understand "all other things in a stereo system being equal."