Hi, long time forum lurker, first time poster here. Been an audio pro for 25 years and I've had my pair of Sennheiser HD600's for 21 of them so I know them inside out. I know they're light in the bass and the best I've gotten was using tone boosters morphit to compensate, but these Slate 'phones immediately told me that they had a more accurate low end and not just extra flabbiness pretending to be detailed low end.

I had a problem with a track which had a subby synth bass layered with a real electric playing an octave higher, I just couldn't get a clear separation, these Slate 'phones did the trick and in 10 minutes I'd fixed the problem which would have taken many trial and errors without them.

Archon midfield for me has an ability to make you set the reverb, delay and general fx balance spot on whilst also being a full range frequency balance fixer, its a very close up presentation which was near perfect for me, the Archon far field were amazing for real depth In the kick and bass. The NRG near field is exactly as I'd hoped and gave a slightly bigger room ambience with all the tonal features of NS-10's. It is uncanny the feeling of depth and space around the direct sound from the 'speakers', I'd used ARS3 (with correct head measurements) before and it was useful in checking bass/sub over the three types of speaker, but the sound seemed ill-defined throughout the spectrum to me and I was guessing more than I'd liked about eq and compression decisions.

For info, as it may help some, my head is 19.2cm from ear to ear and they fit very comfortably, a bit heavier feeling than my HD600's, although smaller in size. The closed back design is welcome as I mix in the spare room of my house and I like to listen quite loud.

When I tried the headphone emulations they all sounded terrible, the 650's were absolutely nothing like my 600's, way too dull by comparison (no idea how 650's actually sound but they were a million miles from the same 'family' sound people say is the difference between them) in fact all of them were not to my liking, the HD linear was interesting and the best (most usable for making decisions) headphone style.

I'm a big 'spike' stent fanboy and his mixes sound amazing on every single speaker model in VSX and they've given me really interesting things to think about on my mixes when switching between the rooms/speakers. Not really had any issues with switching between sets and having weird phasing problems, I seem to be less sensitive to these things! The depth knob had very little impact on the sound for me.

I'd like to thank @ Bose and @ bmanic for their contributions to the threads I've read (although my bank account doesn't!). When people like this put the amount of time they have into testing plugins/gear and giving us high quality feedback to make our own minds up, we should be very grateful.

Good luck to all who buy these 'phones, they've added more to the quality of my productions and mixes/masters in one day than any plugin/softsynth/technique has. Here's to the next few months of really putting them through their paces.