It's good quality, but the Macbook's output gain is far too high, don't you think? With my 2012 rMBP, the noise floor is clearly audible and the sound becomes deafening by the time the volume level reaches about 1/4. An attenuator is definitely required.
Currently doing a bit of critical listening with the UM56 tips. I think the overall sound balance is pretty spot-on with the W60. The W4R sounds "shouty" in comparison.
I watched Captain Phillips with the W60 fed directly from my Yamaha RX-A710 and it sounded absolutely amazing.
Unfortunately my W60 seems to have a manufacturing defect. With the braided cable, the connection on the left earpiece is loose and the audio tends to drop out as the cable moves around. The vendor is sending me a replacement cable but I think the problem is with the socket on the left earpiece.
My 2014 Macbook Pro Retina (13inch) is silent with the W60. I have not heard the 2012 MBP to make any comment. My previous 2010 Macbook Pro was noisy.
Bummer to the loose connection. How did you diagnosed that it was the socket rather than the cable?