While different makes and models of speakers clearly sound quite different and some measure out better than others in instrumented tests, they can only work off the signal fed to them.
The SR 7011 is a decent AVR, so it's likely that better speakers may give you sound quality that you like and enjoy better, i.e., more and deeper bass extension and possibly better tweeters. But i also agree with swampwalker above that amplifier quality can be just as important. And in my experience cables can also make a big difference, although many swear that is "fairy dust".
I am currently running a Denon AVR-X5200, which is pretty high in the Denon lineup, but using a separate class A power amp, which is a Krell FPB-400cx. I do believe the Krell improves the quality of the sound over the built in amp in the receiver. If you know what amp you want to end up with, I guess you could use it with your receiver and see how it compares.
The SR 7011 is a decent AVR, so it's likely that better speakers may give you sound quality that you like and enjoy better, i.e., more and deeper bass extension and possibly better tweeters. But i also agree with swampwalker above that amplifier quality can be just as important. And in my experience cables can also make a big difference, although many swear that is "fairy dust".
I am currently running a Denon AVR-X5200, which is pretty high in the Denon lineup, but using a separate class A power amp, which is a Krell FPB-400cx. I do believe the Krell improves the quality of the sound over the built in amp in the receiver. If you know what amp you want to end up with, I guess you could use it with your receiver and see how it compares.