Question for Amp Designers

We have two Class AB amps with the same power.

One is described as fast, lively, & forward.

The other is described as laid back, mellow, & slower.

What in the design gives these two amps the above sound signatures?  
Hold on a sec- didn't I read an article a while back about all amplifiers with the same rated power and THD sound EXACTLY the same as PROVEN by double blind listening tests?  (My tongue is firmly in cheek) .  Have a Happy Holiday!
"Have you heard this for yourself or are you going by what someone else said?"
"I think its fair to say that we hear it all the time in the world of audio. "

Maybe. But if the OP was going by other people's comments and not by his own observation, then we don't know if the amps really sound like that. There may be no problem at all.

" Yeah, too bad we can't get Julian Hirsch in here to answer this one!"

I'll answer for him.

"We put this amp through our most rigorous tests, and here's what we found out. 

For the first test, we pushed the power button. It passed with flying colors. The amp lit up like a Christmas tree.

The nest test was for sound quality. It passed with flying colors again. We know that all amps sound exactly the same, and this amp was no exception.

In conclusion, we give this amp our highest recommendation. It performed flawlessly during all of our tests. If you're looking for a state of the art amp, this is the one for you.