[ChronicLiar]

I have the worst ears in human history!!!! 

 
^ Just had to point that out that I'm obviously NO audiophile/ headphone expert. I'm just a regular guy who owns 7 different  headphones that are plugged in directly to a Macbook Pro.
 
The top 4 are:
 
ATH m50
SR 325is (GRADO)
Skullcandy's Aviator (Actually a REALLY happy sounding headphone 

)
SENN HD 558
And the others are just CRAP....
 
 
 
Here's the PROBLEM:
I notice that my GRADOs were the best sounding (To me at least) straight out of the box (makes sense because of it's price tag @ 300$). They reached  almost maximum volume with absolutely no distortion. For an open headphone, it was really punchy and full of energy... ( I fell in love)
 
But as they progressed or "Burned in" they started to adopt more of a THINNER sound... I realized by the way, That I was USED to playing music too screw*** loud on my ATH m50s (Closed Back) and I was trying to match that sound with an open headphone  causing a small bit of DISTORTION.  I'm scared maybe they were damaged in this process....

 
 
 
Once I got re- adjusted to "NORMAL" listening levels I hear absolutely no distortion or clipping.... It just sounds thinner than I originally remembered....
 
Could this be caused by the constant high volumes (DAMAGE) ? Or is it that the m50s are just more congested than the grados?

 

[gradofan1]

Four words: get an dac/amp!

 

[SteveHiFi]

It's hard to know what the 'thinness' sound has crept in from, do you have your volume sliders on the mac all the way up? There may be one you turned down and forgot about, you never know. The thin sound is the classic cry for help from underpowered drivers.
 
As above, I'd recommend a DAC/AMP -  this would offer a significant jump in SQ.

 

[cel4145]

It's hard to know what the 'thinness' sound has crept in from . . .

Agreed. It could be psychological, too. No. I'm not saying you are nuts. In the first place, audio memory is unreliable, and 2nd, we tend to adapt to a particular headphone sound. So for instance, I used to have the SR225is. They would sound strange at first if coming from a listening a lot to my car stereo or a set of headphones with a different sound signature.