[david028]

My first love when it come to headphones were the original open backed Sennheiser PX-100s. Warm, fun and fast. Especially the hum behind vinyl tracks and deep vocals such as coldplay's Swallowed In the Sea.
 
These headphones were perfect until I started listening to my dads Grado SR80s!!
 
Now I've heard the next-level quality highs and mids in the Grados I cant go back to the cheaper PX100s
 
Can someone help me find my next headphones?
 
I find the the Grados to be too bright so I think I would be better off with Senns.
I have a budget around the price of the HD598 and I keep reading great reviews of these, and of the HD600. But every time It the same story; "slightly lacking in bass". My open backed px-100 were not lacking in bass at all. 
 
Where can I find a pair of open backed headphone with quality highs, quality mids, without being heavily flavored, too bright or "slightly lacking in bass"?

I listen to a lot of Coldplay, Radiohead, Beatles, Foo Fighters..
I like open backed headphones, I don't care about portability.
I will be buying an amp and listen to vinyl.

 

[buke9]

Another in that price range is HE-400S. Touches all your buttons and a lot easier to drive than the Senns. Just a thought.

 

[tz0531]

Might as well mention another very frequently recommended headphone in the full-sized open back arena, the Philips Fidelio X2.

 

[Music Alchemist]

So...your budget is only $150? (The headphones recommended so far are more expensive.) I was going to recommend the HD 650 until I saw your implied budget. I think your best bet is to get a Philips SHP9500 and equalize it.