The 650 is definitely more "lush" than the 600. The point made here is that every piece of the chain can affect the rest. The M&M to me is a better match for the 650. It is a little on the bright side for the 600.
There is also the matter of training your ears to hear things. It takes some time to learn exactly what you are hearing and what you want to hear. I would recommend "practicing" listen to every type of music, listen to other phones and amps. Teach your brain what make things sound different and then you can decide what it is that you actually like and in the process you will learn what combinations of gear will get you there.
lush probably wasn't the right word for me to use, i was thinking of lush as romantic in a appealing to the senses subtext as in like a lush forest. (romantic/appealing to the viewing senses) unless one doesn't like trees, i suppose.. then it's hardly lush or maybe a beach, i don't know..
but on second thought that doesn't fit and it's not really what i meant, i explained in another post it was more a romantic slow dance in a moment, so... a lush forest probably isn't exactly the same thing haha.
the main thing that swayed me to the 600 (well the price but...) was the innerfidelity comparison
(which backs up what you said about the 650 being a bit more lush, warm, thick)
i can't switch from the hd600 to the 650 with tyll hertsens not recommending to do so.
granted i'm an amateur and i don't know all the technical stuff, i just know what sounds like what to me personally.
fast to me might be slow to another, etc.
Edited by Nowhere - 7/12/13 at 8:26pm