[Solrighal]

That's a shed load of money to make HD 600's sound better. I'd second the ODAC/O2 recommendation. With the money you'll save take a holiday. If you don't like them trade them for something slightly better & far more expensive.

I'm listening to my HD 650's right now through the same rig & it's wonderful.

 

[DrSheep]

Screw vacation, get the CEntrance M8 instead.

 

[Rusty143]

I just got my Sennheiser 600s today! I am just listening to them through an iphone5 and old iPod at this point, as my DAC is in for an upgrade. Surprisingly the old iPod sounds better than the iPhone. The sound was muddy out of the box but has started to open up after a couple of hours of music through them. Any advice on how the sound will change with more hours of music? I am leaning toward a Woo WA3 amp to drive them. Thoughts on this?

 

[ProtegeManiac]

Also, I would really appreciate advice on my sources. If I get a cheap DVD or CD player with a coaxial out, as a transport, I could play CDs through the bifrost or repaired Melior. I also want to use my iPhone 5 as a source. Anyone tried the Pure i20 as a connection for the iPhone 5 and output to a DAC? Other suggestions for linking in the iPhone 5?

 
iPhone5 uses a lightning connector, so even if it works, I'm not too confident about how well it fits on the i20 cradle. If you want one that makes those iPhones compatible as a digital transport as well as keep it upright, you can use a stock Apple dock and another iDevice transport/DAC like the NuForce iDo, which can be found in some sites for a lot less than $200.
 
However, you might want to try this Shanling - it has dedicated inputs for PC-USB (and presumably also Androids with the proper OTG hardware and software) and iOS devices, plus SPDIF inputs; and also it has a discrete Class A headphone amp in it.