How revealing are Grado sr-60s'?

I just bought a pair of these last month and overall they seem like decent headphones, but im still having problems with the overall sound of my system. I dont know if its the phones, or my electronics but im getting a somewhat bright, grainy sound. Electric guitars seem way too thin and dont flow smoothly enough ( cant think of the correct term).The bass seems sort of weak too, with a focus on treble. My amp is an Onkyo TX-8511 and a Toshiba SD-3950. My gear is not high end by any means, but do i really have to buy a $500 cdp and headphone amp to get good sound out of $70 headphones?
THey are pretty revealing. Chances are you are hearing the cheap opamps in the Toshiba. Take your cans to a stereo shop that has decent CDP's and plug into the headphone out of one.
It could also be that your source material is classic rock.
Loads of bad transfers to digital and just originally poor recordings.

Good luck!

Yes, most of the music I listen to is some sort of rock, with about 25 percent classic rock- stuff like Zeppelin, Black Sabbath, Iron Maiden and Metallica. I know these arent the best recordings, but shouldnt they at least sound somewhat smoother with better equipment?

One more thing I noticed with these headphones ( and every speaker ive owned as a matter of fact) is that I have to turn them up way too loud to make them open up, by this point the sound becomes too unbalanced for me to handle. It may be my hearing as I have big ears and have REALLY sensative hearing.
I don't know those headphones, but Grados are supposed to be excellent at their price points. They might be just revealing the flaws in your amp & CDP--sometimes happens when you upgrade one component.....

*do i really have to buy a $500 cdp and headphone amp to get good sound out of $70 headphones?*